Suction pad allows you to secure sharpener to any smooth clean surface - See more at: https://www.amtechtools.com/ProductDetails?prodref=E2525&proddesc=KNIFE-SHARPENER-WITH-SUCTION-PAD&category=APP%5FKNIVES%5FAND%5FSCRAPERS&catdesc=Knives---Scrapers#sthash.1FlrHJX7.dpuf