Bike Separators (sometimes called cradles) are used on our Traveler and Road Runner series receiver hitch racks, and our Baja and F6 Expedition trunk/bumper racks.
They slide on to our support arms, and have a 1" inside diameter
Separators are made from a soft (yet firm!) rubber material and include a handy strap to attach your bike to the separator, and includes an anti-sway block to stabilize bike on the rack
They are sold by the pair; i.e., one pair necessary per bike. $14.95 per pair