This clear 12″ x 20″ polyester Glider allows you to see thru your table. Easy bobbin access, & Includes cutting guide to create your own Feed Dog Hole. Ideal for wide-throated domestic machines and Sit Down Long Arms.  Designed to work on Extension Tables, Ruler Bases and Cabinet Inserts! Secures to surface with micro suction technology. Sold in Tube for Ease of Storage.