Five Sided Brass Clock Key Mainspring Winding Tool Sizes 2 4 6 8 10

New 5 Sided Brass Clock Key This is a new 5 sided even number brass clock key This is used to wind clock mainsprings This key has sizes 2, 4, 6, 8 and 10 The hole sizes are 2.75, 3.25, 3.75, 4.25 and 4.75 mmNew 5 Sided Brass Clock Key This is a new 5 sided even number brass clock key This is used to wind clock mainsprings This key has sizes 2, 4, 6, 8 and 10 The hole sizes are 2.75, 3.25, 3.75, 4.25 and 4.75 mm