4 Pack of Anti Vibration Pads 4" x 4" x 7/8" For stereo, surround sound, sub woofer, speaker, audio blue foam center H/D vibration isolation pads 4 pack of Anti Vibration pads All Purpose Blue composite 4" x 4" x 7/8" 60 PSI max load FREE SHIPPING Applications are endless.... Air Compressors, HVAC, Stereo Equipment, Treadmills etc etc designed for Indoor and Outdoor applications these all purpose pads are resistant to moisture, chemicals and the elements