This is an Aqua Craft grim racer precision metal prop balancer.
Includes: One prop balancer with instruction sheet, O-ring keepers, and three shafts of 1/8 3/16 and 1/4 diameters
Length: 6.3 (155mm)
Width: 3 (75mm)
Height: 2.25 (63mm)
Requires: Dust mask, Eye protection, Small round file, Small flat file, 220 Wet/Dry sandpaper, Scratch pad (red) and Felt tip pen