SCUBA Diving Write Slate with Pencil 360° Swivel Clip. Material: PVC slate, plastic clip with 304 stainless steel use for sea water, Slate Dimensions:15.5×12.7cm/6.1x5inch Slate Material: PVC Use for: Diver use it to communicate and note something when diving under water Advantage:professional writing slate, which is specially designed for underwater, you can paint freely, and erase the wirtten content only by hands, it is duable and enable use many times still keep high quality Made in china