Cast iron head. Large 1-7/8" quill allows greater accuracy. Head casting features a permanently lubricated ball bearing spindle assembly, using four heavy duty ball bearings mounted in an enclosed quill for extended lift. Massive T-slotted production work table. 2-7/8" ground steel column diameter for maximum head and table support. 3-3/8" stroke for deep hole applications. Accurate depth stop for precise hole depths. 5/8" Drill chuck & arbor. Type: 20" Floor Cast Iron Drilling Capacity (max./in.): 3/4 Steel Drilling Capacity (max/in.): 5/8 Quill Diameter (in.): 2-1/4 Quill Travel (in.): 4-3/4 Spindle Taper: 3MT Number & Range of Spindle Speeds (RPM): 12(150,260,300,440,490,540,1150, 50, 1840,2220, 2950,4200) Overall Table Size (in.): 18-1/2x16-1/2 Table Working Surface (in.): 14x16 Column Diameter (in.): 3-5/8 Base Size (in.): 22-3/4 x 17-3/4 Spindle to Base (in.): 43-1/2 Motor: 1-1/2HP, 115V, IPh, 1725 RPM Weight (Ibs.): 321 Capacities for continuous production use will vary based on application.