Is battery post shims profitable to sell on Amazon United States?

The niche generates $91K/yr across 21 tracked products. 0 of 4 products launched in the last 360 days are still selling. 90-day search growth is -14.9%. Flapen's verdict: Skip it (48/100).

How competitive is the battery post shims niche?

19 brands and 25 sellers compete. The top 5 products take 62% of clicks and top 5 brands hold 63% of demand.

What do buyers complain about in battery post shims?

Top complaints mined from reviews: Size-Overall, Thickness, Connectivity-Overall. The return rate is 3.3%.

When does demand for battery post shims peak?

Demand peaks in Jan–Feb; the busiest month runs 1.6× the quietest.

What does it cost to enter the battery post shims niche?

Listings span $3.54–$9.95; the average listing price is $6.41 (sweet spot $15–$100). The average incumbent carries 219 reviews — the moat a new listing must climb.

battery post shims

Skip it

Prices mostly outside the sweet spot ($3.54–$9.95) — this niche doesn't clear our bar today.

Quality gap

Incredible3.9★

avg incumbent rating — lower means beatable quality

Conversion

Great11.9%

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

Review moat

Great218.71

avg incumbent reviews — the moat a new listing must climb

Brand share

Good63%

top-5 brand share — brands hold most of the demand

Returns

Okay3.3%

return rate — above 5% kills the launch gate

Competition

Okay62%

top-5 click share — leaders hold, buyers still browse

Market size

Bad$91K

$91K/yr · 119K searches

Growth

Bad-14.9%

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

Avg price

Bad$6.41

avg listing price — sweet spot $15–$100

Price range

Bad$3.54–$9.95

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

Signals No Dominant Brand Quality Gap

According to Flapen's Amazon United States niche tracking, battery post shims is a $91K/yr Amazon United States market (119K searches/yr). The top 5 brands hold 63% of demand. Demand peaks in Jan–Feb. Verdict: Skip it — 48/100.

Data updated Jul 9, 2026 · scored weekly · How we score niches

battery post shims market data

Units sold / yr: 13K–15K; avg 500–750/product
Revenue / yr: $80K–$96K; units × avg price
Conversion rate: 11.9%
Avg BSR: #384
Page quality: 0%
Prime: 100%
Sponsored: 48%
Out of stock: 0.0%
Avg brand age: 35 months
Avg seller age: 180 days

Competition & brand share

The top 5 products take 62% of clicks — established leaders, but buyers still shop beyond them.

Brands

19 flat

Sellers

Top-5 brand share

63%

Top 20: 100%

Top-5 click share

62%

Top 20: 99%

Open market

30%

BESULEN16%
eMagTech16%
smilfuy15%
QWORK10%
AQEENURA7%
Ampper7%

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -14.9% search growth over the last 90 days.

Peak months: Jan, Feb · busiest ÷ quietest = 1.6×

Open Trend

Top battery post shims 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 21 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

eMagTech 4pcs Car Battery Terminals Shims Clamps Posts Spacer Shims for in-car Audio Video Connectors Silver

eMagTech$9.034.5★57 rev

BESULEN 10PCS Car Battery Post Terminal Shims Auto Lead Terminal Shim Caps with 12 Piece Washers for Top Post Battery Post Ends Repair Universal for Vehicles SUV Truck RV Boat

BESULEN$7.944.4★305 rev

smilfuy 1 Pair Battery Post Shims Pure Lead Anode Cathode Sleeves

smilfuy$4.833.6★324 rev

QWORK Battery Post Shims Cap 4 Pack Terminal Cable End for Positive or Negative Post

QWORK$7.294.1★188 rev

Universal 10PCS Car Battery Post Terminal Shims Kit with Washers - Silver Color Terminal End Repair Accessories

AQEENURA$7.694.0★60 rev

Newest

by launch date

4PCS Car Battery Terminal Shim Kit with 4PCS Washers Positive & Negative Car Battery Post Shims for Worn Batteries Post Repair Lead Cars Batteries Shim for Cars SUVs

EWOJUYE$5.3611 rev

5mo ago

TNAIYH Car Battery Post Terminal Shims with Washers 4PCS Positive & Negative Auto Lead Terminal Converter Shim Caps Vehicle Pure Anode Cathode Sleeves Universal for SUV RV Truck

TNAIYH$5.8512 rev

8mo ago

2 Sets Battery Post Shim Set With 14 Washers - Lead Terminal Shim Caps for Car Battery Repair - Fits Top Post Battery Ends

Quadafy$6.0836 rev

8mo ago

2 Pcs Battery Post Shims Car Battery Terminal Shims Extender Adapter Sleeve Automotive Pure Lead Anode Cathode Cap Spacer for Positive Negative Connection

SISABAMA$4.1530 rev

9mo ago

GAOLAOSY 1 Pair Car Battery Post Shims Pure Lead Auto Positive & Negative Post Converter Shim Caps Anode Cathode Adaptor Sleeve Universal Car Battery Terminal Connection Part Accessories (2PCS)

GAOLAOSY$3.9416 rev

1y ago

What buyers say about battery post shims

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

What buyers love

Quality-Overall15%

“The quality of the soft lead construction is excellent”

Value For Money10%

“Good price”

Battery Life9%

“I can give your battery extra life”

Size-Overall9%

“Fit ok”

Advertised Vs Actual Product8%

“As advertised”

Efficiency7%

“it works great”

Ease Of Use6%

“Fairly easy”

Assembly/Installation3%

“Easy install”

Connectivity-Overall3%

“maximum-contact connection”

Rusts/Corrodes3%

“It's always good to have this since it prevents corrosion”

What buyers complain about

Size-Overall36%

“Does not fit”

Thickness23%

“Would have been better if it were thinner”

Connectivity-Overall3%

“You cannot connect once the covers are on the post”

Durability3%

“would break if I tried too”

Functionality-Overall3%

“Didn't work for me”

Quality-Overall3%

“Cheap”

Ease Of Use2%

“Could not use at all”

Natural Resource Wastage2%

“WASTE OF TIME AND MONEY”

Grip1%

“Needs better grip surface”

Value For Money1%

“Waste of money”

Top return reasons

Size-Overall65%

Advertised Vs Actual Product8%

Thickness4%

Compatibility-Overall4%

Functionality-Overall4%

Defective Material/Parts4%

Quality-Overall2%

Value For Money2%

Material Quality1%

Assembly/Installation1%

Common questions

Is battery post shims profitable to sell on Amazon United States?: The niche generates $91K/yr across 21 tracked products. 0 of 4 products launched in the last 360 days are still selling. 90-day search growth is -14.9%. Flapen's verdict: Skip it (48/100).
How competitive is the battery post shims niche?: 19 brands and 25 sellers compete. The top 5 products take 62% of clicks and top 5 brands hold 63% of demand.
What do buyers complain about in battery post shims?: Top complaints mined from reviews: Size-Overall, Thickness, Connectivity-Overall. The return rate is 3.3%.
When does demand for battery post shims peak?: Demand peaks in Jan–Feb; the busiest month runs 1.6× the quietest.
What does it cost to enter the battery post shims niche?: Listings span $3.54–$9.95; the average listing price is $6.41 (sweet spot $15–$100). The average incumbent carries 219 reviews — the moat a new listing must climb.

battery post shims

battery post shims market data

Competition & brand share

Demand & seasonality

Top battery post shims search terms