To use simply squeeze the lever and the drop the hook into the jaw. The hook will be held solidly in the vise. The hardened steel jaw is designed to cover hooks ranging from tiny size 28 to mighty 5/0 saltwater hooks with no adjustments. Other features: lever with anatomic handle, 360 rotary action with dual precision ball bearings, double diameter handwheel, adjustable rotary tension, locking position to 0, adjustable tying angle, adjustable height. The lever can be set up for both left and right handed use. Supplied with pedestal base, spring material clip, allen keys and instruction manual. 360* rotary action with dual precision ball bearings Adjustable rotary tension Locking knob 0* - 180* Head angle, height & fly tying angle adjustment