Is siamp diaphragm washer profitable to sell on Amazon United Kingdom?

The niche generates £45K/yr across 30 tracked products. 0 of 6 products launched in the last 360 days are still selling. 90-day search growth is -5.7%. Flapen's verdict: Skip it (48/100).

How competitive is the siamp diaphragm washer niche?

17 brands and 38 sellers compete. The top 5 products take 50% of clicks and top 5 brands hold 83% of demand.

What do buyers complain about in siamp diaphragm washer?

Top complaints mined from reviews: Functionality-Overall, Size-Overall, Value For Money. The return rate is 0.9%.

What does it cost to enter the siamp diaphragm washer niche?

Listings span £2.64–£26.64; the average listing price is £8.74 (sweet spot $15–$100). The average incumbent carries 656 reviews — the moat a new listing must climb.

siamp diaphragm washer

Skip it

A small market ($45K/yr) — this niche doesn't clear our bar today.

Returns

Incredible0.9%

return rate — above 5% kills the launch gate

Conversion

Great8.1%

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

Review moat

Good656

avg incumbent reviews — the moat a new listing must climb

Competition

Good50%

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

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Price range

Okay£2.64–£26.64

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

Brand share

Okay83%

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

Avg price

Bad£8.74

avg listing price — sweet spot $15–$100

Growth

Bad-5.7%

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

Market size

Bad£45K

£45K/yr · 63K searches

According to Flapen's Amazon United Kingdom niche tracking, siamp diaphragm washer is a £45K/yr Amazon United Kingdom market (63K searches/yr). The top 5 brands hold 83% of demand. Verdict: Skip it — 48/100.

Data updated Jul 21, 2026 · scored weekly · How we score niches

siamp diaphragm washer market data

Units sold / yr: 6K–8K; avg 100–250/product
Revenue / yr: £52K–£70K; units × avg price
Conversion rate: 8.1%
Avg BSR: #73
Page quality: 0%
Prime: 73%
Sponsored: 43%
Out of stock: 7.4%
Avg brand age: 29 months
Avg seller age: 179 days

Competition & brand share

The top 5 products take 50% of clicks — established leaders, but buyers still shop beyond them.

Brands

17 rising

Sellers

Top-5 brand share

83%

Top 20: 100%

Top-5 click share

50%

Top 20: 90%

Open market

15%

SIAMP46%
Taps2Traps22%
Generic7%
NEKAWA4%
Kaelosyn4%
VBSYUYQ2%
Open — no brand owns it (11 brands, 15%)

Demand

Weekly Amazon search volume, last 20 weeks — -5.7% search growth over the last 90 days.

Open Trend

Top siamp diaphragm washer search terms

siamp flush valve20K/yr +5.9%3.7% conv.
siamp diaphragm washer10K/yr -13.4%16.9% conv.
siamp optima 506K/yr +2.7%0.9% conv.
diaphragm washer4K/yr +45.8%6.8% conv.
siamp optima 497K/yr -41.9%3.4% conv.
siamp5K/yr -12.3%3.1% conv.
twyford toilet cistern spares4K/yr +0.5%1.1% conv.
vitra toilet parts4K/yr -27.4%1.2% conv.
diaphragm washer for cistern float valve3K/yr -12.7%8.1% conv.

All search terms

Top siamp diaphragm washer 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

Pack of 3 Replacement Rubber Ball Valve Washers - Fits All Siamp Fill Valves

Taps2Traps£4.234.4★1,185 rev

2 x SIAMP Diaphragm Inlet Float Valve Washer Rubber 95 95L 99T 99B 99 Duravit Laufen Twyford

SIAMP£4.324.6★4,346 rev

SIAMP 32335510 33A Storm Flush Valve - White

SIAMP£16.654.6★1,549 rev

SIAMP 32499910 Optima 49 Flush Valve - White

SIAMP£18.394.6★1,778 rev

2 x Inlet Float Valve Diaphragm Washer - Spare Rubber Ball Valve WASHERS - Replacement Diaphragm Washer - FITS for All SIAMP Inlet VALVES Black

NEKAWA£3.124.2★280 rev

Newest

by launch date

4 PCS Replacement Rubber Ball Valve Washers 27mm Diameter Cistern Refill Valve Diaphragms Toilet Inlet Float Valve Diaphragm Washer Seals Compatible with Siamp Flush Valve Siamp Diaphragm Washer

Kaelosyn£3.964 rev

3mo ago

2pcs Replacement Toilet Flush Valve Seal Compatible with Siamp Toilet Flush Valves 49 and 50 Flush Valve Rubber Seal Washer Toilet Cistern Seal 43mm X 71mm

YiJianLiangBai£4.761 rev

4mo ago

10pcs Toilet Fill Valve Repair Kit Diaphragm Washer Replacement Compatible With Siamp For Most Toilets Flushing Systems 27mm Diameter

LIUQOBN£5.434 rev

8mo ago

Taps2Traps - Replacement Chrome Toilet Dual Flush Button & 470mm Optima 50 Long Wire Flush Valve Cable Fits Siamp Cable Operated Flush Valves

Taps2Traps£19.025 rev

8mo ago

VBSYUYQ 3 Pack 27mm Diaphragm Washers Siamp Compatible Toilet Fill Valve Gaskets Replacement Ball Valve Diaphragms for Cistern Inlet Valves Fixes Running Toilets & Stops Water Leaks

VBSYUYQ£4.603 rev

10mo ago

What buyers say about siamp diaphragm washer

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

What buyers love

Size-Overall27%

“As described and fitted”

Advertised Vs Actual Product24%

“Exactly What I Needed”

Quality-Overall14%

“Very good exactly what I needed”

Value For Money8%

“This item is worth every penny”

Efficiency5%

“does the job perfectly”

Ease Of Use4%

“Easy to use”

Leak-Proof4%

“Fixed leak in toilet”

Assembly/Installation3%

“a little bit of simple assembly”

Functionality-Overall2%

“does the job perfectly”

Maintenance And Repair2%

“Easy 5 minute fix”

What buyers complain about

Functionality-Overall29%

“Didn't work”

Size-Overall17%

“Does not fit siamp”

Value For Money8%

“Not so cheap after all”

Leak-Proof7%

“Leaks”

Jamming/Clogging6%

“So it constantly overflows”

Thickness5%

“thicker than original”

Quality-Overall4%

“stiill cheap”

Durability4%

“Do not last long”

Strength4%

“These toilet flushes are not strong”

Defective Material/Parts2%

“Not 100 % Out of 5 rubber valves only 3 are usable owing to flaws on contact surfaces”

Top return reasons

Size-Overall55%

Compatibility-Overall11%

Defective Material/Parts10%

Functionality-Overall8%

Advertised Vs Actual Product3%

Leak-Proof3%

Quality-Overall1%

Touch/Button Controls1%

Product Condition1%

Connectivity-Overall1%

Common questions

Is siamp diaphragm washer profitable to sell on Amazon United Kingdom?: The niche generates £45K/yr across 30 tracked products. 0 of 6 products launched in the last 360 days are still selling. 90-day search growth is -5.7%. Flapen's verdict: Skip it (48/100).
How competitive is the siamp diaphragm washer niche?: 17 brands and 38 sellers compete. The top 5 products take 50% of clicks and top 5 brands hold 83% of demand.
What do buyers complain about in siamp diaphragm washer?: Top complaints mined from reviews: Functionality-Overall, Size-Overall, Value For Money. The return rate is 0.9%.
What does it cost to enter the siamp diaphragm washer niche?: Listings span £2.64–£26.64; the average listing price is £8.74 (sweet spot $15–$100). The average incumbent carries 656 reviews — the moat a new listing must climb.