SEK Bond PolySweep Polymeric Sand is a blend of native sands conforming to the ASTM C-144 standard, and polymer binders that once activated allow the joints to expand and contract with the elements such as extreme heat/cold and freeze/thaw cycles. Specially formulated with Clear Set Technology® which uses the highest quality, clearest synthetic polymers, PolySweep will not discolor the surface or leave behind a haze.