We love toys like this Fin Angle Tool! Precision made, It is used for setting fins while glassing. It made to make it super simple to set glass on fins or get fins system angles correct , so they are both perfect. The protractor can go from 0 to 180 degrees in opposite directions and has a lock nut to make sure the angle doesn’t move whilst handling.Use it to measure fin angles – you’ll be amazed how they differ side to side. Get your own angles right first time. Accurate to 1° of offset. Use to ensure centre plugs are set for perfectly vertical. Enhance your accuracy and care. Made from a tough plastic and brass.