Customer Reviews for Oatey Gripper 4 in. Plastic Mechanical Test Plug

The Oatey Gripper 4 in. test plug was too large and did not fit inside of Genova #75144 4" Slab Closet Flange.

Best test plug replacement

No issues; seals well.

I use these for mineral feeders. I generally use them as the top and bottom plugs. I've had some in use for over two years. The pic is of an older design, I no longer put the little piece of pipe in the bottom, I just push the plug farther up in. It works better that way, less built-up.

The staff said there was no product in store to seal a toilet drain when removing a toilet, however when we did an Internet search this came up. I then found it on HD site and it was available in the very store we visited. Ended up ordering from a different location for pickup. It works great after all the back and forth to find it.

Initial viewing: Sioux chief The Gripper 4” Mechanical Test Plug is constructed using durable plastic wedge plates and a sturdy, pliable rubber sealing grommet. The threaded carriage bold and cast wing nut, are both cleanly threaded and operate smoothly. The top plate is 4 9/32” and will prevent it from falling into a 4” opening, while the bottom plate is 3 23/32” that easily fits in a 4” opening. Testing: I constructed a test pipe using 4” PVC piping, stepped down to ¾” steel nipple that I attached a 15 psi test gauge (see photo). I placed the test plug into the open end of the 4” pipe and then pumped in 15 pounds of air. The first test resulted in a fast decompression. I tested for leaks and found them around the plug. I tightened the plug to the maximum, using a set of vice grips and tested again. The second test resulted in a slow leak. I then made sure that the cut on the open end of the 4” PVC was exactly square and tested again. The integrity of the seal remained solid and it held 15 psi for 2 hours. Summary: I found this product to be made with excellent materials, the type that will result in a good long useful life span. Though the grommet is made of nice durable rubber, it is only 5/8” thick and needs to be exactly square against the walls of the pipe, to seal correctly. I would use this mostly for just temporally closing openings.

Works great for what it's designed for. As long as you have a clean, round opening, it will easily and securely seal a toilet drain or other open pipe.

Needed a 3.5" plug on a Sunday and only plumbing stores have that size, and they were all closed. Ground the inner plastic down to fit and crammed the rubber in the opening. It did create a water tight seal in the sewage pipe (no pressure). Replaced it the next day with the proper fitting but it did what was needed for a day.

Perfect for sealing the hole I made in my umbrella base so that I could easily fill it with sand!

This product exceeds all expectations!

Well constructed and perfect fit

I tried just a 3 inch but it works fantastic

This peace fits great and had great help from Joey Q

Just as described. Fit perfect for my needs

We are waiting for a new septic system to be installed. In the mean time, every time we get more than 1” of rain in a 24 hr period, I have sewage flooding the lower level of my house. Someone suggested these. I did have to remove the toilet from the floor, and the sink vanity, but the floor was ruined and I needed to gut the bathroom anyway. So I put these in all the drains on that level, 6 in total. We had over 2” of rain in about 12 hours with no overflow. Hallelujah!

A technician recommended the product. You have the two sizes we needed.