In the early days of cave diving, reels were not available to buy off the shelf. Divers used anything they could, including empty electrical wire spools. When exploring, divers would pay out the line and if they didn't empty the spool it would be left in the cave for the next dive. The spools came in various sizes and North Florida cave diver, Bill Hogarth Main, popularized smaller spools for safety and jump reels. Today, the Dive Rite 120 foot Finger Spool is often used for shooting lift bags as well as a safety reel. Small and low-profile, a spool fits nicely out of the way in a pocket or clipped off to a D-ring.