These Midrange Captive Bearing Traveler Cars do not come with a factory installed purchase configuration for traveler car adjustment. You can add a purchase system to an existing car (up to a max. of 4:1) using the 27 mm Purchase Upgrade Kit (T27K). Proper choice of purchase allows easy adjustment of the car using a single line and no winch. High-strength Torlon ball bearings run on machined, Hardkote-anodized, Teflon impregnated races for smooth trimming and easing. The cars have a simple shackle for attaching the mainsheet block to the car. The car is designed so it is possible to upgrade the shackle to a stand-up toggle, if desired. Use with 27 mm CB Track Available in standard and high-load versions to handle mainsheet loads on boats from 27 ft to 34 ft (8 to 10 m) Solid 6061-T aluminum body for light weight, strength, and durability Captive bearings for easy loading and maintenance Please call us if you have questions regarding gear selection for your boat