Wrist Size Strap Lengths
6.00 to 6.50 --------- 110/70mm
6.25 to 7.25 --------- 115/75mm
7.0 to 7.5 ------------ 120/75mm
7.5 to 8.0 ------------ 125/80mm
These are a general guide to the watch strap sizes needed. We also carry many other watch strap lengths (ex: 130mm/70mm, 140mm/80mm, 150mm/85mm, etc...) Many people tend to get longer straps with more "tail" if they are a casual watch strap and shorter watch straps for dressier watch straps.
2) You will need to measure the inside lugs of your watch in order to know the width of the strap needed.
Panerai Model Watch Strap Width
40 mm Luminor case ----------- 22 mm
44 mm Luminor case ----------- 24 mm
42 mm Radiomir case ---------- 24 mm
44 mm Radiomir case ---------- 26mm
45 mm Radiomir case ---------- 26mm
47 mm case --------------------- 26 mm
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