Adjustable from 22" to 29-1/2" long, the telescoping bike frame adapter secures two bicycles together during transportation. The lock provides added stability for both bicycles and ensures the frames will not bump and scratch each other. Also, the frame adapter can be works great as a temporary female to male bicycle tube for bicycle racks and carrier use. Telescoping Bike Frame Tube Adapter - Female to Male Bicycles * Bicycle frame adapter secures (2) bikes together for travel * Adds a temporary female to male bicycle tube for bicycle racks and carrier use * Adjusts from 22" to 29-1/2", helps reduce damage to bicycle frames * Works as a steady horizontal bar for female bikes (hooked from the seat support to front rotor) * Easy push latch operation