... spines of plastic ring are available.comb binding ring Specification:plastic ring,lustrous surface,strong adhesiveness,endure abrasion and ... bear rusting ,eroding,and aging.comp binding ring Material :Innocuous material,which complies with the environmental safty standards of Occident ... Notebook,album,calendar and so on.comb binding ring Specification: Inside Diameter of Ring(mm)StyleApprox.no.of Sheets ...