---
title: "vacuum caps — Niche Verdict: Skip it (45/100) | Amazon United States - Flapen"
canonical_url: "https://flapen.com/amazon/research/us/automotive/vacuum-caps"
last_updated: "2026-07-13T22:39:50.779Z"
locale: en
meta:
  description: "brand-locked demand (top 5 brands take 98% of clicks) — vacuum caps doesn't clear our bar today."
  "og:description": "brand-locked demand (top 5 brands take 98% of clicks) — vacuum caps doesn't clear our bar today."
  "og:title": "vacuum caps — Niche Verdict: Skip it (45/100) | Amazon United States - Flapen"
---

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# **vacuum caps**

**Skip it**

Brand-locked demand (top 5 brands take 98% of clicks) — this niche doesn't clear our bar today.

Market size 33Growth 50Conversion 96Competition 23Returns 93Price range 36Avg price 47Brand share 4Review moat 72Quality gap 19

**Conversion**

**Incredible****13.2%**

search→purchase rate — share of searches ending in a sale

**Returns**

**Great****1.1%**

return rate — above 6% kills the launch gate

**Review moat**

**Good****603.2**

avg incumbent reviews — the moat a new listing must climb

**Growth**

**Okay****+20.0%**

90-day search growth — must beat 0% to launch

**Avg price**

**Okay****$11.58**

avg listing price — sweet spot $15–$100

**Price range**

**Okay****$6.50–$19.79**

cheapest to priciest tracked listing — scored on the share inside $15–$100

**Market size**

**Okay****$156K**

$156K/yr · 102K searches

**Competition**

**Bad****72%**

top-5 click share — a locked-up shelf

**Quality gap**

**Bad****4.7★**

avg incumbent rating — lower means beatable quality

**Brand share**

**Bad****98%**

top-5 brand share — brand-locked demand

## **Competition**

The top 5 products capture 72% of clicks — a locked-up shelf that new listings rarely crack.

**Brands**

**6 **—flat

**Sellers**

**23**

**Top-5 brand share**

**98%**

**Open market**

**0%**

- Easily59% - BUSY-CORNER29% - ISPINNER4% - BUIYLV4% - Dorman2% - MINIMARU2% - Open — no brand owns it (0%)

## **Product shelf**

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

0%10%$16K20%$31K30%$47K40%$62K101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 15 tracked products in this niche — three views at once, no toggling.

### **Top sellers**

by 90-day click share

[1![Rubber Vacuum Caps Plug Kit 102 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8](https://m.media-amazon.com/images/I/41fbdi9SyQL.jpg)**Rubber Vacuum Caps Plug Kit 102 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8**Easily**$9.09**4.7★1,386 rev](https://www.amazon.com/dp/B09XN2VSZM) [2![Rubber Vacuum Caps Plug Kit 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8](https://m.media-amazon.com/images/I/51f0xij0B+L.jpg)**Rubber Vacuum Caps Plug Kit 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8**Easily**$6.93**4.7★373 rev](https://www.amazon.com/dp/B0CN8K5LGP) [3![BUSY-CORNER 80 Pieces Vacuum Cap Assortment Rubber Dropper ID from 5/32 to 3/8 Sizes Hose Caps Kit for Carburetor Manifold (Black)](https://m.media-amazon.com/images/I/51+l1DENCcL.jpg)**BUSY-CORNER 80 Pieces Vacuum Cap Assortment Rubber Dropper ID from 5/32 to 3/8 Sizes Hose Caps Kit for Carburetor Manifold (Black)**BUSY-CORNER**$7.55**4.7★1,427 rev](https://www.amazon.com/dp/B08YZ55JTS) [4![110 PCS Vacuum Caps Assortment Vacuum Plugs Hose End Cap Rubber Vacuum Caps Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8](https://m.media-amazon.com/images/I/519mSSQSswL.jpg)**110 PCS Vacuum Caps Assortment Vacuum Plugs Hose End Cap Rubber Vacuum Caps Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8**BUSY-CORNER**$10.04**4.7★394 rev](https://www.amazon.com/dp/B0CX1NCHK8) [5![Vacuum Caps Rubber Plug Kit - 202 PCS 8 Size Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8](https://m.media-amazon.com/images/I/51oSZTCG0kL.jpg)**Vacuum Caps Rubber Plug Kit - 202 PCS 8 Size Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8**Easily**$16.01**4.6★361 rev](https://www.amazon.com/dp/B0BDG6V2L5)

**~~View all top sellers →~~**

### **Newest**

by launch date

[![118 Pcs Vacuum Caps Assortment 10 Sizes Rubber Vacuum Caps Kit Vacuum Plugs Hose End Cap for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8](https://m.media-amazon.com/images/I/41vf4+EFpNL.jpg)**118 Pcs Vacuum Caps Assortment 10 Sizes Rubber Vacuum Caps Kit Vacuum Plugs Hose End Cap for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8**Easily**$13.58**40 rev2y ago](https://www.amazon.com/dp/B0CZNNBZNM) [![115PCS Nylon Vacuum Connectors 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit Black](https://m.media-amazon.com/images/I/511IXXMFUjL.jpg)**115PCS Nylon Vacuum Connectors 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit Black**Easily**$14.81**105 rev2y ago](https://www.amazon.com/dp/B0CYSWKX45) [![110 PCS Vacuum Caps Assortment Vacuum Plugs Hose End Cap Rubber Vacuum Caps Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8](https://m.media-amazon.com/images/I/519mSSQSswL.jpg)**110 PCS Vacuum Caps Assortment Vacuum Plugs Hose End Cap Rubber Vacuum Caps Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8 1/2 5/8**BUSY-CORNER**$10.04**394 rev2y ago](https://www.amazon.com/dp/B0CX1NCHK8) [![Rubber Vacuum Cap 177-Piece 12 Sizes Assortment Set Automotive Carb Line & Hose Caps Kit for Carburetor Manifold Automotive 3/16 5/16 1/4 5/32 3/8 1/8 1/2](https://m.media-amazon.com/images/I/51ZrxLye9lL.jpg)**Rubber Vacuum Cap 177-Piece 12 Sizes Assortment Set Automotive Carb Line & Hose Caps Kit for Carburetor Manifold Automotive 3/16 5/16 1/4 5/32 3/8 1/8 1/2**MINIMARU**$18.45**44 rev2y ago](https://www.amazon.com/dp/B0CKP3ZLHT) [![Vacuum Caps Rubber Plug Kit - 202 PCS 8 Size Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8](https://m.media-amazon.com/images/I/51oSZTCG0kL.jpg)**Vacuum Caps Rubber Plug Kit - 202 PCS 8 Size Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8**Easily**$16.01**361 rev3y ago](https://www.amazon.com/dp/B0BDG6V2L5)

**~~View all new products →~~**

### **Trending**

90-day click momentum

[![80PCS Vacuum Hose Caps Connector Assortment 6 Sizes Black Rubber Cap Automotive Topomatic Replacement Parts for Carburetor Vacuum Plugs Intake Manifold Vacuum Fitting](https://m.media-amazon.com/images/I/51PdtPKLh1S.jpg)**80PCS Vacuum Hose Caps Connector Assortment 6 Sizes Black Rubber Cap Automotive Topomatic Replacement Parts for Carburetor Vacuum Plugs Intake Manifold Vacuum Fitting**BUIYLV**$9.21**4.7★**▲ 69%**](https://www.amazon.com/dp/B09879GX9L) [![ISPINNER 60pcs Rubber Vacuum Caps Assortment Kit Hose End Caps for Carburetor Manifold Automotive 3/16 5/32 7/32 1/4 5/16 3/8](https://m.media-amazon.com/images/I/41ukWuc7iWL.jpg)**ISPINNER 60pcs Rubber Vacuum Caps Assortment Kit Hose End Caps for Carburetor Manifold Automotive 3/16 5/32 7/32 1/4 5/16 3/8**ISPINNER**$6.98**4.6★**▲ 24%**](https://www.amazon.com/dp/B09Z6GJCCM) [![Rubber Vacuum Caps Plug Kit 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8](https://m.media-amazon.com/images/I/51f0xij0B+L.jpg)**Rubber Vacuum Caps Plug Kit 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit for Carburetor Manifold Automotive 3/16 5/16 7/32 1/4 5/32 3/8 1/8**Easily**$6.93**4.7★**▲ 11%**](https://www.amazon.com/dp/B0CN8K5LGP) [![BUSY-CORNER 120 Pieces Rubber Vacuum Cap Assortment 10 Sizes Tube OD from 1/8 to 1/2 Sizes Automotive Carb Line Hose Caps Kit for Carburetor Manifold](https://m.media-amazon.com/images/I/51GRlKNM2hS.jpg)**BUSY-CORNER 120 Pieces Rubber Vacuum Cap Assortment 10 Sizes Tube OD from 1/8 to 1/2 Sizes Automotive Carb Line Hose Caps Kit for Carburetor Manifold**BUSY-CORNER**$16.81**4.7★**▲ 10%**](https://www.amazon.com/dp/B098PZNV56) [![115PCS Nylon Vacuum Connectors 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit Black](https://m.media-amazon.com/images/I/511IXXMFUjL.jpg)**115PCS Nylon Vacuum Connectors 63 PCS Assorted Vacuum Plugs Hose End Caps Assortment Kit Black**Easily**$14.81**4.7★**— 1%**](https://www.amazon.com/dp/B0CYSWKX45)

**~~View all trending →~~**

## **Demand & seasonality**

Weekly Amazon search volume, last 104 weeks — +20.0% search growth over the last 90 days.

3K2KSpike '25Spike '26 seasonSepDecMarJunAugNovMarMay

No pronounced peak months · busiest ÷ quietest = 1.7×

## **Reviews**

What buyers praise and complain about, mined from review topics.

### **What buyers love **

**Quality-Overall**31%

*“Good quality, nice selection of sizes, arrived on time”*

**Size-Overall**19%

*“They fit perfectly on multiple vehicles”*

**Advertised Vs Actual Product**18%

*“As advertised”*

**Value For Money**9%

*“Great value”*

**Efficiency**4%

*“Works perfect”*

**Ease Of Use**4%

*“Very handy and complet”*

**Durability**2%

*“Durable”*

**Correct Contents**2%

*“Just what I needed”*

**Socket/Port/Plug**2%

*“Yep they're plugs like they are supposed to be”*

**Material Quality**2%

*“High Quality Materials”*

### **What buyers complain about **

**Durability**43%

*“They are literally falling apart”*

**Leak-Proof**16%

*“practically fell off causing a major vacuum leak”*

**Quality-Overall**11%

*“these are cheap”*

**Rubber Quality**5%

*“Cheap rubber”*

**Hard Feel**4%

*“Too hard”*

**Material Quality**4%

*“I won't use these on my vehicles anymore because the material seems to crack in about 4 to 6 months”*

**Size-Overall**3%

*“Just wish they included more large sizes”*

**Stain Resistance**2%

*“these caps bio-digrade in a few months and become very rubber staining on hands, cloth etc”*

**Strength**2%

*“brittle falling apart”*

### **Top return reasons **

**Size-Overall**64%

**Defective Material/Parts**7%

**Functionality-Overall**5%

**Material Quality**4%

**Compatibility-Overall**4%

**Advertised Vs Actual Product**3%

**Value For Money**3%

**Rubber Quality**2%

**Quality-Overall**1%

**Flexibility**1%