Imperial Worm Gear Tube Bender - 600-ffor 1 4", 5 16", 3 8", 1 2", 5 8" & 3 4" Tube Sizes. 600 F Precision tool for highest quality work. With a 50 to 1 gear ratio and crank with revolving hand grip keeps effort at a minimum. Follow bar eliminates drawing action and keeps tube in virtually perfect round. Adjustable pressure roller positions quickly in index holes. Enclosed gears. Can be clamped in vise or bolted to bench or tripod. Size of kit: 14 x 9 x 6 Includes metal tool case.