Electronic Mounting Arm Clamps are an excellent way to mount anything electronic to your rack system. Each arm is made of 16.5" flat metal stock, attached to a metal rack clamp with a large T handle that fits onto any standard 1.5" rack bar. This gives a rock solid mounting surface for electronics or any large item needing a flat surface for placement. Each arm has adjustable and lockable rubber stoppers to hold items securely in place. Arms sold in pairs. Gibraltar suggests using memory locks with this item.