Bought 2 of these at 20mm for 20mm 3-link bracelets on SD1953 and SD1934. Too wide. Should have bought 18mm not 20mm. This listing should have the same description as listing for the milled clasp link below that states to get a 18mm clasp for 20mm 3-link bracelets on SD1934 and SD1953. 20mm 3-link bracelets taper to 18mm clasp. Have a SD1979 with a 22mm bracelet that does.not taper and has a 22mm clasp. May try fitting getting 20mm spring bars to fit instead of the 18mm spring bars that don't. See description of clasp size on milled one https://www.steeldives.com/collections/other-watch-accessories/products/steeldive-6-micro-adjustment-clasp