TreeFrog Front Wheel Holder L2 Front wheel holder for double bike carriers For quick-release wheels and thru-axle front wheels Used with Elite 2 and Pro 2 carriers As the demand for double bike racks continues to grow and many customers have asked for them, Treefrog has developed the L2 front wheel holder that works with the Elite 2 and Pro 2 racks. The rack comes with a deck, 1 TreeFrog suction cup placed in the center, 2 front wheel holders that can accommodate 9mm quick release wheels as well as 12x100mm, 15x100mm and 15x110mm thru axle front wheels. A standard quick release must be inserted through these thru axles and secured with the QR lever. The 2 TreeFrog suction cups supplied with your Elite 2 or Pro 2 racks must be attached to the deck, 1-1 per side.