Paylak UNIKEY-1E Even Sizes 5 Prong Universal Clock Key for Winding Clocks Universal clock key Used to wind most clocks Even sizes: 5 prong Brass key Sizes: 2.75mm 7/64 in (2), 3.25mm 1/8 in (4), 3.75mm 0.14 in (6), 4.25mm 11/64 in (8), 4.75mm 3/16 in (10)