Popular quality fiberglass backing for making flap disc. backing pad/fiberglass backing/backing pads/flap disc ... plastic bag,then it will be put into durable carton box.At last a certain number of boxes will be put ... .3mm)Inner diameter: 16.3mm,22.3mm(Tolerance:±0.15mm)Outer diameter: 75mm,85mm,90mm,95mm,105(107)mm,115(117 ... backing, flap disc backing Fiberglass backing plate for flap disc making