This Matthews Menace Arm Kit enables you to boom a lighting fixture attached to a 1 1/4" Schedule 40 aluminum pipe speed rail, sold separately, while keeping the light stand out of camera view. The kit includes an ear with a 9.5" anti-sag center post, dual baby pin front mount, and a rear counterweight receiver with a D-ring on top and bottom for connecting a ratchet strap to the bottom of the stand instead of a counterweight bar.