Is boat gas cap profitable to sell on Amazon United States?

The niche generates $81K/yr across 46 tracked products. 1 of 16 products launched in the last 360 days are still selling. 90-day search growth is +120.1%. Flapen's verdict: Worth a look (69/100).

How competitive is the boat gas cap niche?

36 brands and 139 sellers compete. The top 5 products take 32% of clicks and top 5 brands hold 49% of demand.

What do buyers complain about in boat gas cap?

Top complaints mined from reviews: Size-Overall, Quality-Overall, Leak-Proof. The return rate is 4.9%.

When does demand for boat gas cap peak?

Demand peaks in May–Jun–Jul–Aug; the busiest month runs 5.1× the quietest.

What does it cost to enter the boat gas cap niche?

Listings span $6.87–$78.74; the average listing price is $23.24 (sweet spot $15–$100). The average incumbent carries 89 reviews — the moat a new listing must climb.

boat gas cap

Worth a look

Shows a thin review moat (89 avg reviews), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Review moat

Incredible88.7

avg incumbent reviews — the moat a new listing must climb

Growth

Incredible+120.1%

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

Avg price

Incredible$23.24

avg listing price — sweet spot $15–$100

Brand share

Great49%

top-5 brand share — no brand owns this niche

Price range

Great$6.87–$78.74

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

Competition

Great32%

top-5 click share — an open shelf

Quality gap

Great4.3★

avg incumbent rating — lower means beatable quality

Conversion

Good5.2%

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

Returns

Okay4.9%

return rate — above 5% kills the launch gate

Market size

Bad$81K

$81K/yr · 67K searches

Signals Trending No Dominant Brand

According to Flapen's Amazon United States niche tracking, boat gas cap is a $81K/yr Amazon United States market (67K searches/yr). The top 5 brands hold 49% of demand. Demand peaks in May–Jun–Jul–Aug. Verdict: Worth a look — 69/100.

Data updated Jul 24, 2026 · scored weekly · How we score niches

boat gas cap market data

Units sold / yr: 3K–3K; avg 0–100/product
Revenue / yr: $58K–$70K; units × avg price
Conversion rate: 5.2%
Avg BSR: #724
Page quality: 0%
Prime: 91%
Sponsored: 74%
Out of stock: 4.0%
Avg brand age: 41 months
Avg seller age: 177 days

Competition & brand share

Clicks spread well past the top 5 (32% combined) — an open shelf where new products get seen.

Brands

36 rising

Sellers

139

Top-5 brand share

49%

Top 20: 85%

Top-5 click share

32%

Top 20: 71%

Open market

48%

SEACHOICE19%
Perko12%
TUELETFU7%
Kylazer7%
KH8665%
Dairrr Fuuu3%

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — +120.1% search growth over the last 90 days.

Peak months: May, Jun, Jul, Aug · busiest ÷ quietest = 5.1×

Open Trend

Top boat gas cap search terms

boat gas cap25K/yr +129.9%4.5% conv.
boat fuel cap8K/yr +82.5%3.6% conv.
boat gas cap replacement6K/yr +110.9%2.8% conv.
pontoon boat gas cap4K/yr +245.8%2.0% conv.
marine gas cap5K/yr +105.7%4.2% conv.
perko gas cap5K/yr +117.9%5.7% conv.
marine gas cap replacement3K/yr +189.1%3.4% conv.
vented gas caps for boat3K/yr +117.6%2.5% conv.
boat gas tank cap4K/yr +50.3%3.9% conv.
gas caps for boats3K/yr +96.0%2.1% conv.

All search terms

Top boat gas cap products on Amazon

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

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

All 24 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Seachoice Replacement Gas Fill Cap Chrome-Plated Zamak

SEACHOICE$10.934.1★542 rev

Boat gas cap replacement part including valve cap key

Kylazer$38.404.5★31 rev

2 Inch/50mm Boat Gas Cap Stainless Steel Polished Marine Deck Fill with Chain Fuel/Water/Gas Filler Cover Replacement for Boats Yachts Caravans RVs Trucks - Deck Marine Hardware Accessory (Silver)

KH866$14.082.8★8 rev

Fuel Deck Fill Cap Replaces 0126DP0BLK for Perko 1313 and 1314 Series for Seachoice 32011 for Ranger Brass Non-Locking Cap 2 Pcs

TUELETFU$8.854.1★160 rev

SEACHOICE Replacement Gas Fill Cap Non-Locking

SEACHOICE$7.643.9★65 rev

Newest

by launch date

0540DPG99A Boat Gas Cap Marine Fuel Cap for Perko 1-1/2 Angled Neck Vented Fuel Fills Chrome Plated Bronze with Chain O-Ring & Wrench

GYUTONG$35.223 rev

3mo ago

316 Stainless Steel Marine Deck Fill Cap with O-Ring Replaces Compatible with Perko 1313/1314 & for Seachoice 32011 Boat Gas Cap Replacement 1-1/2 Thread for Bass Boats

TurtBluse$10.938 rev

4mo ago

1-1/2 NPT Thread 0540DPG99A Marine Fuel Cap Replacement Gas Cap with O-ring for Angled Neck Vented Fuel Fills Compatible with 0540/0541/0556/0557 Series Vented Fuel Fills

Xiaoyudou$35.154 rev

5mo ago

Boat Gas Cap Replacement for Peko 0540DPG99A Marine Air Cap Cover Fuel Tank Cap with Airtight Seal UV & Corrosion Resistant Heavy Duty Marine Grade Easy ToolFree Installation

Dozont$30.554 rev

7mo ago

0540DPG99A Marine Fuel Tank Cap for Perko 1-1/2 Vented Gas Deck Fill Includes Wrench O-Ring & Chain

Succell$36.018 rev

7mo ago

What buyers say about boat gas cap

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

What buyers love

Size-Overall44%

“Exact fit”

Quality-Overall13%

“Excellent quality, perfect fit, and a solid seal every time”

Advertised Vs Actual Product8%

“As advertised”

Value For Money3%

“Its affordable”

Ease Of Use3%

“is easy to use”

Leak-Proof2%

“it does seem to seal just fine”

Durability2%

“boasts excellent durability”

Material Quality2%

“The material is dense and corrosion-resistant, ensuring the threads won't warp or cross-thread even after seasons under a blistering sun”

Assembly/Installation2%

“Easy to install”

Design-Overall2%

“has a pleasing design”

What buyers complain about

Size-Overall25%

“Super tiny”

Quality-Overall13%

“Didn't like the quality”

Leak-Proof5%

“One of the most common causes of problems with modern engines in boats or cars is a gas cap that is leaking air”

Durability5%

“Broke before first use”

Advertised Vs Actual Product5%

“Not a good description”

Add-Ons/Attachments4%

“Bottom not attached good”

Rubber Quality4%

“The rubber gaskets were not even installed”

Compatibility-Overall3%

“Does not fit old Sea Ray boats”

Defective Material/Parts3%

“The center piece falls off”

Functionality-Overall3%

“does not work”

Top return reasons

Size-Overall86%

Compatibility-Overall4%

Advertised Vs Actual Product3%

Defective Material/Parts2%

Functionality-Overall1%

Leak-Proof1%

Value For Money1%

Assembly/Installation1%

Quality-Overall1%

Software/Application0%

Common questions

Is boat gas cap profitable to sell on Amazon United States?: The niche generates $81K/yr across 46 tracked products. 1 of 16 products launched in the last 360 days are still selling. 90-day search growth is +120.1%. Flapen's verdict: Worth a look (69/100).
How competitive is the boat gas cap niche?: 36 brands and 139 sellers compete. The top 5 products take 32% of clicks and top 5 brands hold 49% of demand.
What do buyers complain about in boat gas cap?: Top complaints mined from reviews: Size-Overall, Quality-Overall, Leak-Proof. The return rate is 4.9%.
When does demand for boat gas cap peak?: Demand peaks in May–Jun–Jul–Aug; the busiest month runs 5.1× the quietest.
What does it cost to enter the boat gas cap niche?: Listings span $6.87–$78.74; the average listing price is $23.24 (sweet spot $15–$100). The average incumbent carries 89 reviews — the moat a new listing must climb.