The foamboard stapler is used to install radiant tubing to a wide variety of foam insulation boards in slab-on-grade or slab-over-slab applications reducing the installation time. It is compatible with Onix tubing sizes 3/8 IN or 1/2 IN, PEX tubing sizes 3/8 IN to 5/8 IN, and RadiantPEX-AL tubing sizes 3/8 IN to 5/8 IN. The stapler is designed to reduce misfires and limit jams. The stapler comes fully assembled and can use either the 1 1/2 IN or 2 1/4 IN size plastic staples. The shorter staples are to be used for 1 IN insulation boards and the longer staples for 2 IN, or thicker, insulation boards. The stapler holds up to 120 staples.