Polymer injection molded. Strong dynema cord and special spring with 0,6 kg force contain. Rotative safety sytem to block the final parts in the case. Double slot loop with adjustable inclination with screws. • 8V30/8V31 with final part rotating system lock • 8V32/8V33 without final part rotating system lock • 8V30/8V32 with Stop & Go system • 8V31/8V33 without Stop & Go system (standard)