Ref. : FBLS.01BC.45 / FBLS.01BC46R1S / FBLS.01BC47 / FBLS.01BC48The model FBLS.01. BC.45 is completely removable. The cutting of the blade is complex but the operation is good. The FBLS.01. BC.46R1S has two springs. Security is essential. Clasp FBLS.01. BC.47 is with a blade that engages in two phases. Aimed at bracelets and pearl necklace. The last clasp of this group FBLS.01. BC.48 is actually a spring-loaded clamp. Very complex, it is better to use a laser for cutting the parts. Need also precision adjustment.