If you have or are familiar with the Dometic holding tank set up that comes on many newer Four Winns cruisers, it has the holding tank vent filter mounted directly on the tank.

It's held on with a strap and a small plastic piece on each side that applies pressure and holds the strap down. One of mine popped off. Dometic wants $30 for the kit, all I need is the small plastic piece the strap goes into then you push down on it, locking it in place. No idea for its technical term so Google is useless to me now.
Has anyone else had to replace this part?