its only true purpose is to prevent against rack rash, it does not isolate equipment from each other, rather it isolates the rack equipment from the rack rails, so if 1 unit is causing hum this will transfer along each unit as their faceplates arent isolated
the screws dont fit my adam hall rack or gator case, it comes with a soft adapter for smaller screws
you have to cut the pieces out of their molds which isnt too difficult, but takes some accuracy to get them looking smooth with no bits sticking out.
the rubber/plastic warps/goes out of shape and shift position before you have the screws tightened, its difficult to gauge when its tight enough, when it feels tight your left with a misshapen piece
I dont normally right reviews straight after using a product but was so let down by these that I felt the need to write a review. some old bicycle inner tube would work better, or 2 plastic washers per screw would achieve the same