Harken's Small Boat Captive Ball Bearing Spinnaker Pole Car is made from one piece of solid aluminum that is hardcoat-anodized and PTFE-coated for strength and durability. It has stainless steel wire guides to keep the ball bearings captive when the cars are off the track.
This 4 63/64 in (127mm) car has ring fittings made of 17-4PH stainless steel, which accept piston pole ends for end-to-endend jibing. The car and rings are engineered to handle the forces of spinnakers as large as 900 square feet (85 square meters).
It has a safe working load of 1,125 pounds (510kg).