FORMAT: Compatible with DoorKing DKProx READER COMPATIBLITY: These wristbands are compatible with the DoorKing 1815-333, 1815-330, 1815-305, 1815-302, 1815-301, 1815-300, 1504-124, 1815-305, and all 18815-xxx readers. SIMILIAR TO: DoorKing DKProx DKProx 1508-120, 1508-121, 1508-112, 1508-123, 1508-111, and 1508-129 cards and fobs. APPEARANCE: Blue Wrist Band: Internal diameter 65mm, Fits the average wrist size. INFORMATION WE NEED FROM YOU FACILITY CODE: Be sure to let us know what facility code you need.