Tyger Auto TG-RK1B108B Deluxe Bike Top Frame Cross Bar Bicycle Telescopic Adaptor - Black 100% assembled. Creates a top tube for non-conventional frames. Ideal for kids bikes women's bikes and sloping down tubes. Keeps your bike mounted solidly on rack arm mounts. New push button clamps for quick installation and removal. Telescopic adjustment for all size bike frames and anti-rotation inserts for greater stability. Durable rubber collars secure easily and safely to bike stem and seat post. Easy installation in seconds. TYGER No-Hassle Limited Lifetime Warranty!