These black plastic rings flex at the end for easy insertion or removal of cross connect cables. The 3/8 in 1/4 turn connector mounts on the front and back of the Mighty Mo racks. It can also be installed into 3/8 in square accessory holes on the sides of the Mighty Mo racks or into any open 3/8 in square EIA mounting hole.
Legrand Mighty Mo 20 Rack System