Wall mounting. Pennsylvania made 1/8in thick aluminum laser cut and formed thread racks, capable of holding 150 spools. This rack is able to hold all 100m spools. The posts are 1-1/2in spaced evenly on centers and each post is 2in long. The provided mounting holes are spaced at 16in centers for easily mounting to wall studs, not all mounting holes are needed. Overall dimensions are 23in Wide x 28.5in High x 1.5in Thick. Threads shown in the pictures are not included.