Don't second guess yourself. The hook looks like a question mark! Nice deep hook so that it doesn't unhook easily. Crimp, knot, or glue, or some combo thereof. Takes a fairly small gauge, I would say. Length is length of closed clasp, both parts together. Lead, nickel and cadmium free.
Lead-free. Nickel-free. Made in Israel. 6mm x 14mm By the each.