Home > Shop > Lumber & Plywood > Plywood & Panels > Underlay Underlay 4x8-8.5mm CANOE FIR UNDERLAY Item #: 01698705 $49.90 Add to Cart 4x8-5/16" ENSTRON UNDERLAY Item #: 01700610 $30.50 Add to Cart 4x8-3/8" ENSTRON UNDERLAY Item #: 01702515 $31.90 Add to Cart