Polylok's stackable bolsters allow for more flexibility when stacking rebar. Our bolsters are available in 44" lengths and can accommodate 3/4", 1", 1-1/4", 1-1/2", 1-3/4", 2", 2-1/4", 2-1/2", 2-3/4", 3", and now 3-1/2", 4", 4-1/2", and 5" heights. Our stackable bolsters can easily be fastened together for longer lengths. Unlike any other bolster on the market, the Polylok's stackable bolsters can be stacked into a multi-level configuration, meeting specific height requirements.