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Fence post plastic black caps for nominal 4X4 fence post that measure 3-5/8"x 3-5/8" ~ See images for comparison. Important: your post must measure 3-5/8" x 3-5/8" -if you post measures a true 4x4, this cap will not fit, please see our additional listing for True 4x4 100mm Fence Cap.

There won’t be fading, our plastic post caps are UV and heat-resistant, highly durable, impact-resistant, and weatherproof plastic, cracking for years to come!. And the best part? These plastic post caps don’t look tacky. Made from high-quality and durable plastic - fence post plastic caps need to withstand extreme changes in weather.
8 more fence post caps for the same price - this is probably the most affordable pack of fence post plastic caps in the market! For the same price as 16-pack fence post caps, you have 24 plastic caps you can use both on your fence and deck posts! With their sleek and timeless appeal, these fence post caps will definitely add a stylish touch to your home’s exterior. Moisture seeping into the end grain can easily half the posts’ lifespan. Once planed, each side would be around 3 5/8 inches. There are 3 options in securing the caps to the posts: nails, ensure that said adhesive will bond on both plastic and wood.


Durable aluminum construction- once installed, these metal post caps are practically maintenance free! The weather resistant aluminum construction is designed to handle the outdoor elements, and features a powder-coated finish to add a touch of style to any spot in your backyard.
Simple install - stop messing around with those complicated installations. This set includes eight post caps. Dress up your yard - let's be honest, fences can be boring and not the best item in your yard to look at. Designed for wood posts - designed to specifically fit on a 4 x 4 nominal wood post, the GreenLighting Aluminum Pyramid Post Cap is your one-stop solution for dressing up those plain fences.

Please take time to measure your post not all 4x4 post are the same dimension. Dimensions - measures approximately: inside dimension: 3-5/8” x 3-5/8 inches; Inside Total Depth of Cap: 1-1/4 inches; Slant Width: 1 inch; Inside Cap Edge Height Edge that Covers Post: 1/2 inch.

Pyramid design also fits standard 4x4 mailbox, lamp post, deck, dock and piling posts. Protects your post tops from rain and sun to prevent premature rotting! Warranty lifetime warranty by weatherPRO Post Caps.


Our single base fit any 3. 5-5 inch square or round wooden post. It will withstand harsh heat, and snow. See product images. Ip44 waterproofsolar fence post light has an ip44 waterproof rating and is made of tough ABS plastic.
Even in the daytime, it is a good decoration. You can rest assure to use, heavy downpour, in any outdoor environments. What you getbrand-new product, Excellent quality, Support 30-days worry-free refundand and friendly customer service. One size fits all wooden posts come in all shapes and sizes.

Fit fits 3. 5" x 3. 5" 4" nominal standard wood post. Single-pack 1 one gloss black powder Coated Post Cap with screws made of sturdy cast aluminum.
1. Deckorators
#ad
Deckorators 72213 Newport Classic Treated Post Cap 4x4
#adDeckorators #ad - Inside dimensions are 3-5/8” x 3-5/8”. Pressure treated for durability. For use with posts measuring 3-1/2 inch x 3-1/2 inch. Measures 4” x 4”.More information #ad
Brand | Deckorators #ad |
Manufacturer | Deckorators #ad |
Height | 3 Inches |
Length | 6 Inches |
Width | 6 Inches |
Part Number | 72213 |
Model | 72213 |
Warranty | 90 day limited warranty |
More information #ad
2. JSP Manufacturing
#ad
JSP Manufacturing Plastic New Fence Post Black Caps 4X4 3 5/8" Pressure Treated Wood Made in USA MULITPACK Wholesale Bulk Pricing 24
#adJSP Manufacturing #ad - Can be painted, must use a paint that adheres to plastic. Please take time to measure your post not all 4x4 post are the same dimension. 4x4 3-5/8" x 3-5/8" plastic black fence post Caps ~ Multi-pack Quantity Item - Please verify correct quantity needed.Fence post plastic black caps for nominal 4X4 fence post that measure 3-5/8"x 3-5/8" ~ See images for comparison. Important: your post must measure 3-5/8" x 3-5/8" -if you post measures a true 4x4, this cap will not fit, please see our additional listing for True 4x4 100mm Fence Cap.
More information #ad
Size: inside dimension 3-5/8" x 3-5/8" square ~ 1/8-inch-thick to protect your treated posts from water and sun damage. Installation: must be secured with nails or an adhesive that bonds to plastic and wood, should be pre-drilled if securing with nails. Cap presses over the outside of a 4x4 Post, a little flex but will not stretch.Brand | JSP Manufacturing #ad |
Manufacturer | JSP Manufacturing #ad |
Height | 50 Centimeters |
Length | 100 Centimeters |
Weight | 100 Kilograms |
Width | 100 Centimeters |
More information #ad
3. TonGass
#ad
TonGass 24-Pack 4x4 3 5/8" Fence Post Caps, Protect Wooden Fence Poles Outdoor in Low Profile, Made from Black Durable Plastic
#adTonGass #ad - Easy to install and secure fence post caps - the black caps will slip easily on top of the posts. With inside dimensions of 3 5/8 inches by 3 5/8 inches and an edge height of 1/2 inch, these black plastic fence post caps will fit perfectly on most fence posts. For both nails and screws, the caps will flex enough to fit, you’ll need to drill a pilot hole in at least two sides of the caps.There won’t be fading, our plastic post caps are UV and heat-resistant, highly durable, impact-resistant, and weatherproof plastic, cracking for years to come!. And the best part? These plastic post caps don’t look tacky. Made from high-quality and durable plastic - fence post plastic caps need to withstand extreme changes in weather.
More information #ad
Even when the post is a few millimeters bigger, and adhesive. Black plastic post caps for 4x4 3 5/8” fence posts - most 4x4 fence posts actually have nominal dimensions of 3 1/2 inches by 3 1/2 inches. 8 more fence post caps for the same price - this is probably the most affordable pack of fence post plastic caps in the market! For the same price as 16-pack fence post caps, you have 24 plastic caps you can use both on your fence and deck posts! With their sleek and timeless appeal, these fence post caps will definitely add a stylish touch to your home’s exterior. Moisture seeping into the end grain can easily half the posts’ lifespan. Once planed, each side would be around 3 5/8 inches. There are 3 options in securing the caps to the posts: nails, ensure that said adhesive will bond on both plastic and wood.
Brand | TonGass #ad |
Manufacturer | TonGass #ad |
Part Number | 4" x 4" |
More information #ad
4. Deckorators
#ad
Deckorators 72889 Newport High Pyramid Treated Post Cap
#adDeckorators #ad - For use with posts measuring 3-1/2 inch x 3-1/2 inch. Inside dimensions are 3-5/8” x 3-5/8”. Measures 4” x 4”. Durable pressure treated base.More information #ad
Brand | Deckorators #ad |
Manufacturer | Deckorators #ad |
Height | 3 Inches |
Length | 6 Inches |
Weight | 0.5 Pounds |
Width | 6 Inches |
Part Number | 72889 |
Model | 72889 |
Warranty | 90 day limited warranty |
More information #ad
5. GreenLighting
#ad
GreenLighting 4x4 Aluminum Pyramid Post Cap Cover for Nominal Wood Posts Brown, 8 Pack
#adGreenLighting #ad - Greenlighting has kept it simple by providing you with pre-drilled bases and all the mounting screws needed to get your cap set up right out of the box. Specifications - measures 3. 63" x 3. 63"and is designed to fit a 4" x 4" nominal wood post.Durable aluminum construction- once installed, these metal post caps are practically maintenance free! The weather resistant aluminum construction is designed to handle the outdoor elements, and features a powder-coated finish to add a touch of style to any spot in your backyard.
More information #ad
Not suitable for PVC or Vinyl posts. But with the quick addition of a post cap, you can add a touch of style to your fences or walls to make them really stand out. Simple install - stop messing around with those complicated installations. This set includes eight post caps. Dress up your yard - let's be honest, fences can be boring and not the best item in your yard to look at. Designed for wood posts - designed to specifically fit on a 4 x 4 nominal wood post, the GreenLighting Aluminum Pyramid Post Cap is your one-stop solution for dressing up those plain fences.
Brand | GreenLighting #ad |
Manufacturer | GreenLighting #ad |
Height | 9.75 Inches |
Length | 4.75 Inches |
Weight | 2.38 Pounds |
Width | 4.75 Inches |
Part Number | TN-1219664 |
More information #ad
6. JSP Manufacturing
#ad
JSP Manufacturing 16 Pack Fence Post Plastic Black Caps 4X4 3 5/8" Pressure Treated Wood Made in USA
#adJSP Manufacturing #ad - Must be secured with nails or an adhesive that bonds to plastic and wood, should be pre-drilled if securing with nails. Cap presses over the outside of a 4x4 3-5/8" x 3-5/8" post, a little flex, but will Not Stretch.Please take time to measure your post not all 4x4 post are the same dimension. Dimensions - measures approximately: inside dimension: 3-5/8” x 3-5/8 inches; Inside Total Depth of Cap: 1-1/4 inches; Slant Width: 1 inch; Inside Cap Edge Height Edge that Covers Post: 1/2 inch.
More information #ad
Inside dimension 3-5/8" x 3-5/8" square, 1/8-inch-thick to protect your treated posts from water and sun damage. These caps for nominal 4x4 fence post that measure 3-5/8"x 3-5/8". 4x4 3-5/8" x 3-5/8" plastic black fence Post Caps - 16 Pack.Brand | JSP Manufacturing #ad |
Manufacturer | JSP Manufacturing #ad |
Weight | 1.23 Pounds |
Part Number | FBA_FC-4x4-BLACK-16 |
Model | FBA_FC-4x4-BLACK-16 |
More information #ad
7. WeatherPRO Post Caps
#ad
Dock, Piling Caps, Lamp Post, 4x4 Fence Post Cap 3 1/2" 4 Pack White Powder Coated Aluminum, Mailbox, Deck, Replacement Guarantee
#adWeatherPRO Post Caps #ad - Fit fits 3. 5" x 3. 5" 4" nominal standard wood post. Why buy plastic when you can install aluminum? Protects our aluminum fence post caps won't deteriorate or warp like wood, plastic or resin will.Pyramid design also fits standard 4x4 mailbox, lamp post, deck, dock and piling posts. Protects your post tops from rain and sun to prevent premature rotting! Warranty lifetime warranty by weatherPRO Post Caps.
More information #ad
Multi-pack 4 four gloss white powder Coated Post Caps with screws made of sturdy cast aluminum. Ornamental decorative & attractive - Classy look dresses up your fence, deck or dock! Please measure first - does not fit TRUE 4"X4" POSTS.Brand | WeatherPRO Post Caps #ad |
Manufacturer | WeatherPRO Post Caps #ad |
Height | 50 Centimeters |
Length | 100 Centimeters |
Weight | 100 Kilograms |
Width | 100 Centimeters |
Part Number | FPC5 |
More information #ad
8. WeatherPRO Post Caps
#ad
Never Have to Replace These Premium Post Caps Made with Solid Aluminum. Powder Coating Never Fades, Sold by U.S. Company., WeatherPRO Black 4x4 Fence Post Caps 3.5” 4 Pack
#adWeatherPRO Post Caps #ad - Ornamental decorative & attractive - Classy look dresses up your fence, deck or dock! Multi-pack 4 four gloss black powder Coated Post Caps with screws made of sturdy cast aluminum. Pyramid design also fits standard 4x4 mailbox, deck, lamp post, dock and piling posts.More information #ad
Protects your post tops from rain and sun to prevent premature rotting! Warranty lifetime warranty by weatherPRO Post Caps. Why buy plastic when you can install aluminum? Protects 4x4 aluminum fence post caps won't deteriorate or warp like wood, plastic or resin will. Fit fits 3. 5" x 3. 5" 4" nominal standard wood post.Brand | WeatherPRO Post Caps #ad |
Manufacturer | WeatherPRO Post Caps #ad |
Part Number | FPC1 |
More information #ad
9. POWGDLT
#ad
Deck or Garden Decoration, POWGDLT Solar Post Cap Lights Outdoor 10 Lumen Double LED Fence Post Solar Powered Waterproof Light-One-Fits-All Base for 4x4 or 5x5 Wood Posts in Patio, 12 Pack Black
#adPOWGDLT #ad - Easy to installthe solar post cap lights 5. 2" x 5. 2" x 3. 9". Avoid the cost of hiring electricians or handymen, the base is fixed by the provided screws, no need to connect wires, environmental protection and saving.Our single base fit any 3. 5-5 inch square or round wooden post. It will withstand harsh heat, and snow. See product images. Ip44 waterproofsolar fence post light has an ip44 waterproof rating and is made of tough ABS plastic.
More information #ad
Fit baseif the universal base doesn't like it, we can ship the corresponding base. Beauty by designthese bungalow style post cap lights add radiance and distinction to gardens, or decks, yards, creating a well-lit path to your outdoor environment. Even in the daytime, it is a good decoration. You can rest assure to use, heavy downpour, in any outdoor environments. What you getbrand-new product, Excellent quality, Support 30-days worry-free refundand and friendly customer service. One size fits all wooden posts come in all shapes and sizes.
Brand | POWGDLT #ad |
Manufacturer | POWGDLT #ad |
Height | 3.86 Inches |
Length | 5.24 Inches |
Width | 5.24 Inches |
Model | SL1717-12P |
More information #ad
10. WeatherPRO Post Caps
#ad
Replacement Guarantee, Mailbox, Deck, Piling Caps, Lamp Post, Dock, 4x4 Fence Post Cap 3 1/2" Single Pack Black Powder Coated Aluminum
#adWeatherPRO Post Caps #ad - Pyramid design also fits standard 4x4 mailbox, lamp post, deck, dock and piling posts. Protects 4x4 aluminum fence post caps won't deteriorate or warp like wood, plastic or resin will.Fit fits 3. 5" x 3. 5" 4" nominal standard wood post. Single-pack 1 one gloss black powder Coated Post Cap with screws made of sturdy cast aluminum.
More information #ad
Ornamental decorative & attractive - Classy look dresses up your fence, deck or dock! Protects your post tops from rain and sun to prevent premature rotting! Warranty lifetime warranty by weatherPRO Post Caps. Please measure your posts prior to ordering. Why buy plastic when you can install aluminum? .Brand | WeatherPRO Post Caps #ad |
Manufacturer | WeatherPRO Post Caps #ad |
Part Number | FPC8 |
More information #ad