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52

m12 ワッシャー

Worth a look

Shows low returns (0.3%), but pricing outside the sweet spot ($668.07 avg) keeps it on the watch list.

Market size 57Growth 35Conversion 53Competition 42Returns 99Price range 0Avg price 0Brand share 49Review moat 83Quality gap 75

Returns

Incredible0.3%

return rate — above 5% kills the launch gate

Review moat

Great349.96

avg incumbent reviews — the moat a new listing must climb

Quality gap

Great4.3★

avg incumbent rating — lower means beatable quality

Market size

Good¥438K

¥438K/yr · 15K searches

Conversion

Good4.3%

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

Brand share

Okay75%

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

Competition

Okay60%

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

Growth

Okay+8.3%

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

Avg price

Bad¥668.07

avg listing price — sweet spot $15–$100

Price range

Bad¥273.36–¥979.73

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

According to Flapen's Amazon Japan niche tracking, m12 ワッシャー is a ¥438K/yr Amazon Japan market (15K searches/yr). The top 5 brands hold 75% of demand. Verdict: Worth a look — 52/100.

Data updated Jul 31, 2026 · scored weekly · How we score niches

m12 ワッシャー market data

Units sold / yr
750–1K
avg 0–100/product
Revenue / yr
¥501K–¥668K
units × avg price
Conversion rate
4.3%
Avg BSR
#90
Page quality
0%
Prime
87%
Sponsored
74%
Out of stock
3.5%
Avg brand age
55 months
Avg seller age
191 days

Competition & brand share

The top 5 products take 60% of clicks — established leaders, but buyers still shop beyond them.

Brands

16 rising

Sellers

55

Top-5 brand share

75%

Top 20: 100%

Top-5 click share

60%

Top 20: 96%

Open market

21%

  • トラスコ中山(TRUSCO)25%
  • オノカツ\FASTENER & MECHANICAL PARTS21%
  • Aurooooa18%
  • FregocS6%
  • デイトナ(Daytona)4%
  • POTRRCIUSUER4%

Demand & seasonality

Weekly Amazon search volume, last 85 weeks — +8.3% search growth over the last 90 days.
400300Spike '25Spike '26JanFebMarAprMayJunJulAugSepOctNovDecJanFebMarAprMayJunJul

No pronounced peak months · busiest ÷ quietest = 1.4×

Top m12 ワッシャー 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.

0%10%¥44K20%¥88K30%¥131K40%¥175K1101001K10K Reviews — right = deep review moat Market share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 23 tracked products in this niche — three views at once, no toggling.

What buyers say about m12 ワッシャー

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

What buyers love

総合品質24%

“良い商品だと思います。”

コストパフォーマンス23%

“コスパがいい”

漏れ防止18%

“オイル漏れなどトラブルなく使えてます。”

使用の容易さ9%

“普通に使えます”

メンテナンスと修理8%

“オイル交換の準備をする際、「あ、予備があったな」と思える安心感は絶大です。”

圧力3%

“適正トルクで”

厚み3%

“元々付いてる物よりも倍の厚みが有りコレなら漏れる心配が無く安心です。”

組み立て/インストール3%

“問題なく、取付け出来ました。”

機能全体3%

“何の問題も無く使えています。”

サイズ全体2%

“サイズもぴったりで、問題なく取り付けでき安心して作業ができました。”

What buyers complain about

総合品質25%

“安い”

不良材料/部品13%

“消耗品なので. オイル交換の度に変える消耗部品なので.”

潤滑13%

“オイルが滲んできました”

漏れ防止13%

“漏れました。きつく締め直しても漏れます。”

厚み13%

“ダイハツウェイク ドレインパッキン使用 厚さがあるが普通に使える”

サイズ全体6%

“こういった部品は小さくて見落としがちですが”

傷に強い6%

“写真のように細かい傷がたくさん入っています。”

耐久性6%

“耐久性はまだ分かりませんが現状特に問題はありません。”

Top return reasons

サイズ全体36%
広告と実際の製品の違い23%
互換性-全体14%
不良材料/部品9%
商品の状態9%
総合品質5%
耐久性5%

Common questions

Is m12 ワッシャー profitable to sell on Amazon Japan?
The niche generates ¥438K/yr across 23 tracked products. 1 of 2 products launched in the last 360 days are still selling. 90-day search growth is +8.3%. Flapen's verdict: Worth a look (52/100).
How competitive is the m12 ワッシャー niche?
16 brands and 55 sellers compete. The top 5 products take 60% of clicks and top 5 brands hold 75% of demand.
What do buyers complain about in m12 ワッシャー?
Top complaints mined from reviews: 総合品質, 不良材料/部品, 潤滑. The return rate is 0.3%.
When does demand for m12 ワッシャー peak?
Demand is steady year-round — the busiest month runs 1.4× the quietest.
What does it cost to enter the m12 ワッシャー niche?
Listings span ¥273.36–¥979.73; the average listing price is ¥668.07 (sweet spot $15–$100). The average incumbent carries 350 reviews — the moat a new listing must climb.