On my frig shelves, on each side of the shelf, I drilled a small pilot hole thru the shelf and into the plastic wall the shelf mounts to. I then screwed a small stainless screw thru the shelf and into the wall.
This prevents the shelves from bouncing out and also adds a little structural integrity to the shelves.
1999 Fleetwood Southwind 35S (Ford F53 6.8L V10 275hp 4R100 4 spd trans) - Toad 2003 Saturn Vue.
It won't do MACH 2, but I can get a sandwich and take a pee.