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59

延長コード 50cm

Worth a look

Shows a $5.9M/yr market, but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Market size 98Growth 21Conversion 79Competition 61Returns 98Price range 0Avg price 0Brand share 52Review moat 53Quality gap 60

Market size

Incredible¥5.9M

¥5.9M/yr · 88K searches

Returns

Incredible0.4%

return rate — above 5% kills the launch gate

Conversion

Great8.0%

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

Competition

Good49%

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

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Review moat

Good1,389.11

avg incumbent reviews — the moat a new listing must climb

Brand share

Good74%

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

Growth

Bad-7.1%

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

Avg price

Bad¥835.71

avg listing price — sweet spot $15–$100

Price range

Bad¥358.98–¥2205.12

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

According to Flapen's Amazon Japan niche tracking, 延長コード 50cm is a ¥5.9M/yr Amazon Japan market (88K searches/yr). The top 5 brands hold 74% of demand. Demand peaks in Jan–Nov–Dec. Verdict: Worth a look — 59/100.

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

延長コード 50cm market data

Units sold / yr
6K–8K
avg 100–250/product
Revenue / yr
¥5.0M–¥6.7M
units × avg price
Conversion rate
8.0%
Avg BSR
#72
Page quality
0%
Prime
89%
Sponsored
67%
Out of stock
6.5%
Avg brand age
48 months
Avg seller age
180 days

Competition & brand share

The top 5 products take 49% of clicks — established leaders, but buyers still shop beyond them.

Brands

16 rising

Sellers

64

Top-5 brand share

74%

Top 20: 100%

Top-5 click share

49%

Top 20: 94%

Open market

20%

  • オーム(OHM)28%
  • サンワサプライ(Sanwa Supply)15%
  • エレコム(ELECOM)12%
  • TESSAN11%
  • KOZATO8%
  • ANPEI-ELEC6%

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -7.1% search growth over the last 90 days.
5K4KSpike '24Holiday '24Prime Day '25Spike '25Black Friday '25Spike '26SepDecMarJunAugNovMarMay

Peak months: Jan, Nov, Dec · busiest ÷ quietest = 2.2×

Top 延長コード 50cm search terms

  • 延長コード 50cm46K/yr
  • 延長コード 0.5m22K/yr
  • 延長コード0.5m6K/yr
  • 延長コード 0.55K/yr
  • 延長コード 50cm 黒4K/yr
  • 延長コード 短い 0.5m4K/yr
All search terms

Top 延長コード 50cm 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%4%¥235K8%¥469K12%¥704K16%¥939K1101001K10K100K Reviews — right = deep review moat Market share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

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

What buyers say about 延長コード 50cm

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

What buyers love

使用の容易さ18%

“机まわりをすっきりまとめやすいUSB付き電源タップ”

コストパフォーマンス10%

“お手頃価格”

サイズ全体10%

“大型アダプターもスムーズに収まる”

充電8%

“あくまでスマホの夜間充電などのおまけ程度として割り切って使っています。”

コネクタ/ポート/プラグ7%

“USB-Aも含めてポート数があるので、充電器をいくつも持ち歩かなくて済むのは助かります。”

総合品質6%

“信頼出来るメーカーのようです”

デザイン全体4%

“シンプルでコンパクト”

強さ4%

“手堅い商品”

持ち運びやすさ4%

“シンプルでコンパクト”

セキュリティ4%

“安心感”

What buyers complain about

厚み12%

“ケーブルは太く固め。”

耐久性7%

“すぐ使えなくなった”

総合品質6%

“安い”

サイズ全体6%

“50cmでは短かった。”

コネクタ/ポート/プラグ4%

“極性付きプラグは物理的に使用できません”

広告と実際の製品の違い4%

“商品ページにプラグ形状の詳細説明がない点は不親切に感じました。”

使用の容易さ3%

“取り回しがしづらいのがややネックです。”

デザイン全体3%

“余計なデザイン”

測定/読み取り精度3%

“よく計測する必要はあると思う。”

メカニズムの問題3%

“コンセントの入れ換えで抜いてみたら固かったので。見たら若干曲がってました。”

Top return reasons

サイズ全体17%
互換性-全体14%
コネクタ/ポート/プラグ11%
不良材料/部品9%
広告と実際の製品の違い9%
機能全体7%
総合品質6%
充電5%
磁力/吸着力4%
使用の容易さ3%

Common questions

Is 延長コード 50cm profitable to sell on Amazon Japan?
The niche generates ¥5.9M/yr across 27 tracked products. 2 of 4 products launched in the last 360 days are still selling. 90-day search growth is -7.1%. Flapen's verdict: Worth a look (59/100).
How competitive is the 延長コード 50cm niche?
16 brands and 64 sellers compete. The top 5 products take 49% of clicks and top 5 brands hold 74% of demand.
What do buyers complain about in 延長コード 50cm?
Top complaints mined from reviews: 厚み, 耐久性, 総合品質. The return rate is 0.4%.
When does demand for 延長コード 50cm peak?
Demand peaks in Jan–Nov–Dec; the busiest month runs 2.2× the quietest.
What does it cost to enter the 延長コード 50cm niche?
Listings span ¥358.98–¥2205.12; the average listing price is ¥835.71 (sweet spot $15–$100). The average incumbent carries 1,389 reviews — the moat a new listing must climb.