The ATB 100 amplifier ceiling mounting kit is an adjustable two-piece metal bracket, used to mount Extron plenum-rated audio power amplifiers above ceiling tiles utilizing Extron C‑ring / V‑rail tile bridges. The mounting bracket length is adjustable to accommodate different rail‑to‑rail spacings used by various ceiling speaker sizes from 3" to 8". A secondary attachment point is provided for seismic security.