Works perfectly fora 3 strand 18 necklace. I have three chains with pendants that are all the same length. Easy open clasps for each chain. Magnets grab each other with no fumbling.

Magnet is strong. Does the job but a lil heavy. One downside is that the closure is kinda heavy for thinner chains so it drags the necklace down a little bit.

Although the clasps function as intended, the weight of the magnet and clasp itself pulls the necklaces to drape in the back. This clasp is heavy and didn't actually solve the problem of tangled chains.