Reproduction strobe disk as found on two-speed Rek-O-Kut turntables such as the L-34. Center area is precisely sized to fit over the pop-up 45s adapter on platter. Printed on white 70-pound text paper, as original. No adhesive backing. Use your X-acto knife or a sharp pair of scissors to cut out, then either lay it in place or affix with spray glue or double-sided tape. Two disks provided in case you mess up cutting the first one. :-)