Handy tool for feathering spinwing fins. It's very simple and practical to use: the arrow snaps into the tube, and the graduated grooves allow you to draw reference lines for gluing the fins; The graduated scale is repeated on each of the ferritories in order to simplify the line drawing.

NOTE: in order to make the structure more stable when printing, small separators have been inserted in the middle of each slot; these small supports have the task of making the structure more stable as it is printed in height; at the end of printing these can be left or removed with a cutter