Borrelly 360° internal (designed for bore) and external (designed for shaft) multi turn spiral retaining rings are manufactured by coiling the ring from laminated flat wire with round edges.

Borrelly Spring Washers is manufacturing  spiral retaining rings from 5 mm to 1000 mm, from 1 to 7 turns in austinetic stainless steel AISI 301 – AISI 302 – AISI 316 – or structurally hardened such as  17-7 pH cond.C, and also Inconel, Hastelloy or CuBe2.