Tech Cork is a firmer synthetic cork used mostly for key regulation in Musical Instrument Repair. It is a much firmer cork that will not compress over time like natural cork. It is harder to cut with a razor blade than natural cork, but makes a longer lasting repair under key feet. Can be sanded like natural cork. We use contact cement to adhere it to metal keys. Assortments include on of each size sheet. TechCork - Sheets - (125 mm x 100 mm) - Sheets Full (125mm x 100mm) and Half Sheet assortments (125mm x 50mm) of TeckCork in 13 thicknesses. .3mm through 1.0mm in .1mm increments, 1.2mm,1.5mm, 1.8mm, 2.0mm, 2.6mm.