Don't be mistaken by the name and think of attaching a tow line to this spinnaker pole ring.
Schaefer's Spinnaker Slider fits on a 1 in. (25mm) x 3/16 in. (5mm) T-track and is adjusted up and down on the track by pulling lines attached to the eyes welded to the upper and lower ends of the grade 316 stainless steel car. It has a 7/16 in. (11mm) ring stock with a 2 in. (51mm) interior ring diameter and is 5 5/16 in. (135mm).