Fermus Shower Floor Drain Insert Drain Plug Anti-Odor Plug Sewer Core One Way Drain Valve Backflow Preventer for Basement Drain, Suitable for Drain Tube 1.5-1.77in, Minimum Drain Depth 2in (Gold)

Fits a 1.5” diameter ABS pipe. Inside diameter. Very easy to install. Spray a little silicone on seal, slides right in. It is made of brass so it won’t rust out. This will definitely prevent backflow from your sewer system.

Worked perfectly for what I needed. Definitely took care of the smell coming out of my drain in my shower.

The item fits snug in the shower drain hole. The water flows down the drain with no problem. The best part and reason why we got the device, the bad odors from the drain pipe do not come through. Perfect solution to a big odor problem.

Flap did not open properly leaving pool of water at the bottom of the sink slow drain instead of a open flush. But it looks good🫣

I bought a pair for the bathroom drain, the width of the hole is 3.1 cm. So it did not fit. After altering the width of the drain it fitted good and works well. No regrets in buying them.