CSK20 One-Way Clutch Ball Bearing - 20mm Sprag Freewheel BackstopCSK20 One Way Clutch Ball Bearing 20x47x14mm Sprag Freewheel Backstop The CSK20 one way clutch bearing is made for applications where rotation should happen in only one direction. It works like a freewheel or backstop, letting shafts spin forward while locking instantly if they try to reverse. This type of bearing is commonly used in conveyors, textile machines, printing presses, washing machines, and any setup where rollback could cause damage like