Made of plastic material, lightweight, anti-corrosion and durable Unique design blank finger spool is perfect for those divers that have line and their own clips to use Small and compact size, easy to use Large diameter center hole for comfortable bare hand use and use with cold water gloves Great gear equipment for cave diving, technical diving activities and a wide variety of diving applications Specification: Material: Plastic Outer Diameter: Approx. 7.7 cm / 3 inch Thickness: Approx. 3.2 cm / 1.26 inch Center Slot Diameter: Approx. 2.5 cm / 0.98 inch Fit 31 m / 102 ft Package Includes: 1 Piece Scuba Diving Finger Spool Note: Please allow slightly difference due to manual measurement. Color may be slightly different since different monitor. Thanks!