im pretty sure he means the ones that fit together almost like some kinda puzzle
i bet hes having trouble with putting them on cuz i dont think they slide on like most rails do. i know when i was putting those segmented rail covers on my 416 and my brothers kirenex they were extremely hard to get on the rail. i had to pound them on with a block of wood and rubber mallet
i dunno if you can but try putting them together and then tapping them down on the rail if they fit together off the rail
these ones?