The Crain Power Stretcher has the features that you would expect in a more expensive power stretcher. Comes complete with adjustable locking power head, Auto-Lok tube, 3 extension tube sections, 1 transfer tube section, folding tail block, and your choice of cases. Adjusts from 37" to 23 ft. and can be lengthened by adding additional extension tubes (No. 502). The No. 500 has an adjusting knob on the top of the power unit with a visual depth setting gauge. Just set the dial to the desired pin depth and you're ready to stretch.