Green Drain™ · 3.5″/4″ · DN90-100

Green Drain™ 3.5″/4″
Combo seal.

Name: Green Drain™ 3.5"/4" Combo
Brand: Green Drain
SKU: GD-3.5/4
Price: 48.99 EUR
Availability: InStock

3.5 and 4 inches / DN90–DN100 / internal grate diameter 90–100 mm

Second combo variant — fits both 3.5″ and 4″ gullies. Optimal for large facilities where gully sizes are mixed between 90 and 100 mm.

€48.99 · VAT included

Price excluding VAT: €39.19

In stock · dispatched from our Croatian warehouse · 5–8 working days to Ireland

Need a formal quote, volume pricing, or delivery to several sites?Request a quote →

Price includes VAT. Delivery to Ireland is calculated in the cart from weight and item count, and shown before you pay. Businesses with a valid VIES VAT number are invoiced without VAT under the reverse charge.

VAT-exempt intra-EU invoice (Art. 138)For businesses

HACCP Int. RG-04NSF/ANSI 2SGS QDF25-0049810-01CE ETA-18/0536EU MDR 2017/745 (Class I)ASSE 1072-2020CSA B79-2008cUPC IAPMO 9301

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Technical specification

Green Drain™ 3.5″/4″ (GD-3.5/4) — silicone seal with ABS frame. All manufacturer specifications.

Size

3.5″/4″ (DN90-100)

Seal material

Medical silicone

Frame material

UV and chemical resistant ABS

Built-in unit height

50 mm

Maximum flow

323.17 L/min

Temperature range

−40 °C to +100 °C

Seal life

About 5 years in normal use

ASSE 1072 cycles

2,500+ test cycles

Aerosol Blockage (SGS)

99.9 % MS2 surrogate

Packaging

1 piece in a box + instructions

Weight

110 g

What is Green Drain™?

Patented one-way silicone seal that is installed in the body of an existing floor drain. Under the weight of water it opens downward, and at rest it remains hermetically sealed upward — physically blocking sewer gases, viral aerosols, and insects.

No water in the P-trap, no chemicals, no maintenance. Medical-grade silicone, proven long-lasting durability, SGS-tested to block >99.9 % of MS2 viral surrogates.

Learn more about Green Drain™ →

Installation in 30 seconds.

No plumber needed. No tools. No cutting into existing pipes. DIY or professional installation.

Step 1

Take off the grate.

Remove the existing grate or strainer from the drain.

Step 2

Insert Green Drain™

Lower the silicone seal 5–10 cm into the drain body.

Step 3

Press into place

Silicone ribs adjust to the diameter. It works immediately.

Step 4

Refit the grate

Done. Thirty seconds' work, lasting protection.

Questions about this size.

What customers ask about the GD-3.5/4.

GD-3.5/4 silicone ribs are expanding — they compress and expand inward until they fill the gully. They seal at both the smaller (3.5″) and the larger (4″) diameter.

No. The GD-3.5/4 passes 323.17 L/min — more than a normal load delivers at once. The seal opens downward under the weight of the water.

Wet cloth for regular floor cleaning. The seal remains in the drain; the grate is removed from above it. Visual inspection once a year.

Yes. Silicone is resistant to sodium hypochlorite up to 5 %, quaternary amines, isopropanol, and ethanol at standard food service and hospital concentrations.

Yes. Green Flow d.o.o. is the authorised distributor of Green Drain™ for Ireland and Northern Ireland. Each unit comes with the manufacturer's original QR code and serial number.

Not sure if 3.5″/4″ is your size?

Send us a photo of your gully and our technical support will recommend the exact size — free of charge, the same business day.

GD 3.5–4″ fits a drain body with an internal diameter of 90–100 mm. If your measurement falls in that range, this is your size.

Lift the grate

Take out the existing grate or strainer. Underneath is the drain body — the pipe the seal drops into.

Measure the internal diameter

Measure the pipe opening, not the grate. The grate is always wider, and that is the single most common reason people order the wrong size.

Match it to a range

Find the size whose range your measurement falls into. If you are between two, take the smaller one — the silicone ribs expand.

No tape measure to hand? A strip of paper works: wrap it around the opening, mark where it overlaps, measure that length and divide by 3.14. And if you still get the size wrong, there is a 14-day return — send it back and we swap it, no questions.

Green Drain™ 3.5″/4″
Combo seal.