4 prong to 3 prong adapter
Skip itA small market ($42K/yr) — this niche doesn't clear our bar today.
Brand share
Great43%top-5 brand share — no brand owns this niche
Avg price
Great$19.26avg listing price — sweet spot $15–$100
Competition
Great37%top-5 click share — an open shelf
Review moat
Good660.2avg incumbent reviews — the moat a new listing must climb
Price range
Good$6.79–$26.34cheapest to priciest tracked listing — scored on the share inside $15–$100
Conversion
Good4.8%search→purchase rate — share of searches ending in a sale
Returns
Okay4.7%return rate — above 5% kills the launch gate
Quality gap
Bad4.7★avg incumbent rating — lower means beatable quality
Growth
Bad-18.1%90-day search growth — must beat 0% to launch
Market size
Bad$42K$42K/yr · 46K searches
According to Flapen's Amazon United States niche tracking, 4 prong to 3 prong adapter is a $42K/yr Amazon United States market (46K searches/yr). The top 5 brands hold 43% of demand. Demand peaks in Oct. Verdict: Skip it — 46/100.
Data updated Jul 27, 2026 · scored weekly · How we score niches
4 prong to 3 prong adapter market data
- Units sold / yr
- 2K–3K
- avg 0–100/product
- Revenue / yr
- $39K–$48K
- units × avg price
- Conversion rate
- 4.8%
- Avg BSR
- #248
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 96%
- Out of stock
- 0.9%
- Avg brand age
- 42 months
- Avg seller age
- 204 days
Competition & brand share
Clicks spread well past the top 5 (37% combined) — an open shelf where new products get seen.Brands
30 falling
Sellers
35
Top-5 brand share
43%
Top 20: 92%
Top-5 click share
37%
Top 20: 76%
Open market
51%
- Strightinc12%
- CircleCord9%
- EXCELFU8%
- WimiSom8%
- WELLUCK6%
- CircleRiver6%
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -18.1% search growth over the last 90 days.Peak months: Oct · busiest ÷ quietest = 1.6×
Top 4 prong to 3 prong adapter search terms
- 4 prong to 3 prong adapter21K/yr
- 3 prong to 4 prong adapter9K/yr
- 30 amp 4 prong to 3 prong adapter9K/yr
- 4 prong adapter4K/yr
- 30 amp 3 prong to 4 prong adapter3K/yr
- generator adapter 4 prong to 3 prong598/yr
Top 4 prong to 3 prong adapter 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.
All 24 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Strightinc 4 Prong to 3 Prong Dryer Plug Adapter with Green Ground Wire Connects 4-Prong New Dryer Female to 3 Prong Old Dryer Male Receptacle 10-30P to 14-30R Dryer Adapter
Strightinc$22.664.8★1,038 rev
1.5FT 3 Prong to 4 Prong Dryer Adapter 4 Prong to 3 Prong Dryer Adapter NEMA 14-30P Male to 10-30R Female Dryer Cord Adapter 4 to 3 Prong STW 10AWG 30A 250V
WimiSom$16.894.8★3,143 rev
Welder Adapter Cord NEMA 14-50P Male to 6-50R Female RV Plug 50 Amp 4 Prong to 3 Prong Welder Plug Adapter 50 Amp 125/250V Electrical Welding Power Adaptor Heavy Duty STW 8 AWG 12500 Watt ETL Listed
EXCELFU$22.374.7★133 rev
WELLUCK 1.5FT 3 Prong to 4 Prong Dryer Adapter 3 to 4 Prong Dryer Plug Adapter 4 Prone Dryer Outlet Adapter 14-30P Male to 10-30R Female Receptacle for Old Clothes Dryer Converter 30A 250V
WELLUCK$22.764.8★3,213 rev
CircleRiver 4 Prong to 3 Prong Generator Transfer Switch Adapter Cord NEMA L5-30P to L14-30R 30 Amp Generator Adapter Twist Lock STW 10 AWG
CircleRiver$19.584.7★405 rev
Newest
by launch date
Deeklify 1.5 ft 10AWG 4 Prong to 3 Prong Dryer Adapter 4 to 3 Prong Dryer Plug Adapter NEMA 10-30P to 14-30R with Green Ground Wire 30A 250V 7500W Heavy Duty SRDT for New Dryers ETL Listed Black
Deeklify$20.7828 rev
Deeklify 1.5 ft 3 Prong to 4 Prong Dryer Adapter 10 AWG NEMA 14-30P to 10-30R Heavy Duty 3 to 4 Prong Dryer Plug Adapter 30A 250V 7500W for Old Dryer Conversion Black SRDT ETL Listed
Deeklify$18.2975 rev
ELEGRP 30 Amp Generator to RV Adapter Cord NEMA L14-30P to TT-30R 4 Prong to 3 Prong Generator Adapter Plug Heavy Duty Dogbone Electrical Converter Twist Lock Male for Camper Travel Trailer 1FT
ELEGRP$19.9722 rev
Suplevel 3 Prong to 4 Prong Dryer Adapter NEMA 10-30P Male to 14-30R Female 3 Prong Old Dryer Plug to 4 Prong New Dryer Connector 30A 250V STW 10 AWG ETL Listed
Suplevel$23.0492 rev
PlugSaf 10 Gauge 1.5FT 30AMP 125V/250V 4 Prong to 3 Prong Dryer Adapter NEMA 10-30P Old House to 14-30R New Dryer with Green Ground Wire Dryer Plug Adapter 4 to 3 Prong Outlet STW ETL Listed
PlugSaf$20.7131 rev
Trending
90-day click momentumPlugSaf 10 Gauge 1.5FT 30AMP 125V/250V 4 Prong to 3 Prong Dryer Adapter NEMA 10-30P Old House to 14-30R New Dryer with Green Ground Wire Dryer Plug Adapter 4 to 3 Prong Outlet STW ETL Listed
PlugSaf$20.714.6★
Deeklify 1.5 ft 10AWG 4 Prong to 3 Prong Dryer Adapter 4 to 3 Prong Dryer Plug Adapter NEMA 10-30P to 14-30R with Green Ground Wire 30A 250V 7500W Heavy Duty SRDT for New Dryers ETL Listed Black
Deeklify$20.785.0★
FGIEU 6AWG 50A 1.6FT 4 Prong to 3 Prong Dryer/Oven/Stove Plug Adapter Converter with Grip Handle NEMA 10-50P to 14-50R STW 3/C Heavy-Duty Cable | 125/250V - NOT FIT EV
FGIEU$24.074.6★
ELEGRP 30 Amp Generator to RV Adapter Cord NEMA L14-30P to TT-30R 4 Prong to 3 Prong Generator Adapter Plug Heavy Duty Dogbone Electrical Converter Twist Lock Male for Camper Travel Trailer 1FT
ELEGRP$19.974.8★
Suplevel 3 Prong to 4 Prong Dryer Adapter NEMA 10-30P Male to 14-30R Female 3 Prong Old Dryer Plug to 4 Prong New Dryer Connector 30A 250V STW 10 AWG ETL Listed
Suplevel$23.044.7★
What buyers say about 4 prong to 3 prong adapter
What buyers praise and complain about, mined from review topics.What buyers love
“As described”
“Good quality device”
“Excellent fit”
“Good deal”
“Easy peasy”
“Sturdy Adapter”
“works perfectly from generator to panel box”
“Durable and Easy to Use”
“Plug”
“Works perfect”
What buyers complain about
“Didnt work”
“It is pretty small”
“Not for RV”
“Plug N' Play”
“These are NOT UL approved”
“This is a false statement however”
“May find it diffcult to connect it”
“Storage bag was not included”
“Defective”
“everything is fine except the price too high”
Top return reasons
Common questions
- Is 4 prong to 3 prong adapter profitable to sell on Amazon United States?
- The niche generates $42K/yr across 46 tracked products. 2 of 4 products launched in the last 360 days are still selling. 90-day search growth is -18.1%. Flapen's verdict: Skip it (46/100).
- How competitive is the 4 prong to 3 prong adapter niche?
- 30 brands and 35 sellers compete. The top 5 products take 37% of clicks and top 5 brands hold 43% of demand.
- What do buyers complain about in 4 prong to 3 prong adapter?
- Top complaints mined from reviews: Functionality-Overall, Size-Overall, Compatibility-Overall. The return rate is 4.7%.
- When does demand for 4 prong to 3 prong adapter peak?
- Demand peaks in Oct; the busiest month runs 1.6× the quietest.
- What does it cost to enter the 4 prong to 3 prong adapter niche?
- Listings span $6.79–$26.34; the average listing price is $19.26 (sweet spot $15–$100). The average incumbent carries 660 reviews — the moat a new listing must climb.