Rat Blocker Rat Flap 100mm – 110mm Non Return Valve

£35.00 £34.30

Title Range Discount
Sewerstore Bulk Discount 0 - 4 2%
Sewerstore Bulk Discount 4 - 6 5%
Sewerstore Bulk Discount 6 - 10 7%
Sewerstore Bulk Discount 11 - 15 10%
Sewerstore Bulk Discount 16 - 20 13%
Sewerstore Bulk Discount 21 + 16%


Rat Blocker Rat Flap 110mm 4″ Non Return Valve For use in sewers as a rodent protection device.

Please note this is for the valve only if you require in deep chambers you will require our optional fitting kit and a pole, this is for a single valve only.

Our Rat Blocker 110mm non return valve is designed for use in sewers it can be inserted in the branch outlet or can be inserted into the chamber outlet in effect one valve protecting all branches within the chamber.

The Rat Blocker non return valve is universal in design as the wire retaining cable can be placed either.

The Rat Blocker Rat Sewer Flap is made from 316 Stainless Steel body and Flap and also a Heavy Duty 316 Marine hinge.

The Wire retaining cable is also 316 marine grade ensuring long life within sewers.

When deciding which rat blocker non return valve you should purchase the grade stainless steel used is extremely important, please see below a overview of stainless steel grades (please note our rat blocker use 316 grade)

Drain rat sewer flap 304 grade is the most common form of stainless steel used around the world.

It contains between 16 and 24 percent chromium and up to 35 percent nickel—as well as small amounts of carbon and manganese. The most common form of 304 stainless steel is 18-8, or 18/8, stainless steel, which contains 18 percent chromium and 8 percent nickel.

316 grade is the second-most common form of stainless steel. It has almost the same physical and mechanical properties as 304 stainless steel and contains a similar material make-up.

The difference is that 316 stainless steel incorporates about 2 to 3 percent molybdenum, which increases corrosion resistance—particularly against chlorides and other industrial solvents. Alternative 300-series grades can contain up to 7 percent molybdenum.

316 stainless steel is commonly used in many industrial applications involving processing chemicals, as well as high-saline environments such as coastal regions and outdoor areas where de-icing salts are common.

Due to its non-reactive qualities, 316 stainless steel is also used in the manufacture of medical surgical instruments.

We decided to use 316 grade stainless steel with our Rat Blocker  to increase the longevity of the product. If you have any further questions please contact us on our phone 01793 630768 or email [email protected]



  1. Florin Pop (verified owner)

    Verified reviewVerified review - view originalExternal link

    Good quality

  2. David R. (verified owner)

    Verified reviewVerified review - view originalExternal link

    Very happy with the quality of the product and very easy to install

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