Using the centrifuge fiberglass sound-absorbing as basical material, frame can be plastic, resin ... curing , aluminum alloy frame 1. Feature:1) Using the centrifuge fiberglass sound-absorbing as basical material, frame can be plastic, resin ... 15mm, 20mm, 25mm,50mm. 3. Angle patterns: Square, rounded, beveled . fiberglass sound-absorbing board