A seatbelt retractor has a spool. An energy absorption mechanism absorbs energy from the spool during seatbelt protraction. The energy absorption mechanism has at least a first portion for a relatively high rate of energy absorption and preferably a second portion for a relatively low rate of energy absorption. The seatbelt retractor has an outer sheath cast, molded, coated or otherwise bonded to and encircling a portion of the external surface of the first portion or the second portion which upon a sufficient exposure to rotational energy breaks the bond between the first portion or the second portion and the outer sheath.