Shower Floor Drain Backflow Preventer, Waterless Trap Seal, One Way Drain Valve Sewer Core (1.28-1.58 inch, Blue)

I bought a 120 year old farmhouse and in the garage, it has drains in the floor. However, this was the era before traps were put in these floor drains and as such, the smell was overwhelming. I saw these and wondered if they would really work. Seriously, I cannot say enough good things about this little gadget. It worked PERFECTLY! I really wondered if it would stop the smell, yet let water flow. Both happen flawlessly. Just be sure your order the correct size and when you insert it into the drain, be sure you don't get it curled. Even if your pipe curves like mine, it still will work. Just gently lay it in so the back flow preventer follows the contour. It will stop any and all sewer gas and smells instantly! I have poured a few gallons of water down to test it and the water flows without any restriction. This is one of the smallest things that has brought so much relief. Definite 5/5 star indeed.

Worked perfect for a test project I was working on.

The instructions were good, but some parts were still hard to understand. When you need to expand it, do you need the big metal piece, expander, then the small metal piece? Should have an exploded diagram of what it is. It does seem to be preventing the sewer gas - primary goal. We just have to use lower volume of water, or the drain cant keep up and it pools in the shower. I have 1.5" shower drain which calls for the small kit, but wondering if the next size up would work better...

This is a great product. After a bathroom renovation last year we have been struggling with sewer smell even though the p-trap was installed properly, etc. This inexpensive seal has stopped the smell for very little investment. LOVE IT

Been frustrated with drain odor for quite some time, this was an easy solution.