The locking heads on Prolok rebar and mesh chairs mean that no bar ties are required — the worker just snaps the rebar into place. The high-chair design will accommodate two perpendicular rebars. A Sandplate base is available that adds stability when pouring over a sand base; it won’t puncture plastic vapor barriers. Cost ranges from 33 cents to $1.06 per piece.

Grip-Rite, 800/676-7777, grip-rite.com.