Quik Trak®1-1/2 in x 4 ft plywood panels are attached to an aluminum heat transfer sheet. Use with 5/16 in Wirsbo hePEX tubing only. A fully assembled set consists of six panels fastened together with strapping tape. The panels are staggered (2 in) on both ends to aid alignment. Uponor Quik Trak® Hydronic Panel, 48 in Length, 7 in Width, For Use With: 5/16 in Wirsbo hePEX™ Plus Tubing, 1/2 in Thk, Plywood, Domestic