HEAVY DUTY: Designed for bookshelf speakers weighing up to 55Ibs ADJUSTABLE: clamp fits speakers from 135mm (5.3") to 280mm (11") wide. PRECISE POSITIONING: Mounts will tilt 7° up or down and swivel up to 180° for perfect speaker placement and acoustics. EASY INSTALLATION WITH MOUNTING HARDWARE INCLUDED: Includes hardware necessary to easily mount into stud/concrete/brick/stone walls. Wall cover included for professional looking installation.