The SK range of foot mounting rail supports (mounting blocks) for the SFC range precision linear rails are available from 12 to 30mm bore from stock.
SK-12 is designed to 12mm-diameter support precision round rail
SK-13 is designed to 13mm-diameter support precision round rail
SK-20 is designed to 20mm-diameter support precision round rail
SK-25 is designed to 25mm-diameter support precision round rail
SK-30 is designed to 30mm-diameter support precision round rail