6-Shot Consumer mortar rack component. Comes with 6 HDPE plugged mortar tubes 12" long, rack sleeve, 4 washers and 4 star knobs. Measures 17 1/2" long and about 3" wide. For use with all consumer aerial shells. The tubes are black and has an ID of 1.91" For use with the ARC End Boards (fits into any of the 3 positions).