Product name:Fiberglass Backing Plate Materials: High purity Fiberglass cloth with phenolic resin Surface layer:With black paper or nonwoven cloth Type: T27, T29 Size: 75mm, 85mm, 90mm, 95mm, 105mm, 108mm, 115mm, 118mm, 140mm, 170mm Layers: Normally it ranges from 5-12 layers, or as per customers' other requirement. Size and shape standard:Our fiberglass backing plate are produced strictly in accordance with the related requiremet of DIN ISO 15635 standard for Flap discs.