Blocks - Cribbing

"Cribbing" is the term used for 2 x 4 x 12 inch pieces of wood, usually made from construction grade pine two by fours. They're primarily used in conjunction with dolly wedges to create a level base for  dolly track.  However, they also come in handy on set for adjusting height of small objects and other tasks.

This industry standard 2" x 4" wood block cribbing is rented by the crate which holds about 50 pieces.