Durable ABS flex bracket for new construction (16-inch (406mm) on-center installations only) can be stapled to studs before drywall is cut and installed. The speaker then installs using its   Roto-Lock clamps. It can be used with all Visual Performance Series, Original Series and Contractor Series Medium round speakers. Not recommended when wall interior obstructions (studs, pipes, etc.) are closer than 1 1⁄4″ (32mm) to the top or bottom of the drywall cut-out hole, or when drywallers must use routers.ription