The “4” standard model is well suited to tieing most trout, small saltwater, and steelhead patterns. The tension adjustment mechanism is set with a gold cross shaped tension adjuster. Each model has four teflon washers to use in the event that the bobbin (spool) end is uneven or has a rough surface. Tip – use one washer on each side of the bobbin (spool) in the event the spool is not turning smoothly. Complete instructions are included on the back of the package card. Item# 2301