- Re-usable Polyurethane Drain Hole Knockout.
- Place on a sink mold to create a hole for the drain.
- Creates a 1-1/2" diameter hole, 1" deep, and then flares out to a 2-3/4" diameter that is 1/4" deep.
- Shape of the Drain Plug has a larger diameter hole on underside of the concrete to allow room for mounting brackets of drain hardware.
- Slightly angled sides to allow for removal from the finished concrete.
- Made of extremely durable Polyurethane. Good for hundreds of uses.
- 1 1/2" Tall, 1 1/2" Diameter Hole x 2 3/4" Diameter (Mounting Hardware Area)
- Secure Knockout in place with a small dab of silicone. Apply Form Release (sold here) to the rubber knockout before pouring the concrete around it to make removal easier later.
- Removal- Prior to flipping over your cured concrete, loosen the edges of the Knockout with a flat head screw driver. Once the concrete piece is turned over, you should be able to push the Knockout free with your thumb and very little pressure. In the event a rubber plug is difficult to remove from the concrete, the center of the rubber plug can be drilled out, giving the plug a little more flex so it can be pushed out easier.
- To Clean- Scrape off any hardened concrete and/or silicone.
Not a perfect shape. The round shapes are not round but irregular eliptic. This is mot made for sharp crafters. The two round shape are even not align in center. I had high expectation with ltd but i am very disapointed
Thank you Marc for your review. These drain hole knockouts are less than perfect, but are not designed to be visible, they are simply used to make a hole in the bottom of a concrete sink that already has a flange area built into the mold. So this product, the 1.5' Drain Hole Knockout is just to make a hole in the concrete, and perfection isn't necessary on these plugs. IF you are looking for a knockout plug that makes the recessed area for the actual metal drain piece to sit in, that is a different product and we make them very precise and round- this product can be seen here: https://www.expressions-ltd.com/products/drain-flange-mold-piece-bathroom-size
Thank you, Expressions-LTD