sand disc. 1.Polished woodware corner groove,rust cleaning,artware. 2.Material:Aluminium oxide. 3.Grit:60--400# 4.color:red sand disc Product features: Brown fused alumina,resin neutral soft cloth. Main application: Furniture,paint,woodware,artware,wood corner and groove burnishing. Grit:60#--400#Outer dia:100mmInner dia:16mmSize:4'Material:Aluminium oxide