Joints between concrete slabs are one of the most vulnerable areas in any concrete flooring installation. That's especially true when it comes to heavy-duty, industrial facilities with heavy machinery traffic. 4920 Polyurea Joint Filler is formulated for use as a semi-rigid joint filler. It is supplied in a 600ml dual-cartridge tube to ensure the proper amounts are mixed through a static tip to get the proper blend for a fast-setting semi-rigid product.