
They are made of hard plastic and are only designed for thin areas. They are quite difficult to use as plastic doesn't fit as well as rubber. I would have given less stars but the description says they are plastic and fit very thin metal. Can't complain too much. As for them, however, they work, but hardly. Not a fan of that. Instead I would advise you to find rubber stoppers.

π§Ό Efficient Cleaning with Canplas 193064 Flush Cleanout - 4 Inch Diameter
9 Review

π Marinco 6365CRN Locking Plug 250V: Secure and Reliable Power Connection Solution
9 Review

π Kreg P OAK Plugs Pocket Hole 50 Pack
7 Review

Continental ContiVikingContact 7 195/65 R15 95T winter
21 Review