Riser Block, Compatible Table Hole Size 5/8 in, Compatible With Buildpro Welding Table, Features Lower Base is Slotted for Adjustable Mounting, Top and Bottom Plates are 0.47 in Thick and Front Sides are 0.12 in Thick, Use the Top Holes for Mounting the Squares in a Fixed Location, Overall Depth 3.5 in, Overall Height 8 in, Overall Length 2 in, Overall Width 5.5 in, Product Type Economy Stop and Clamping Squares, Work Surface Pattern (2) 5/8 in Hole on Top and Bottom, (5) Hole On Side