Tension Spring. Models: HS 81 R HS 81 RC-E HS 81 R-Z HS 81 T HS 81 TC-E HS 81 TC-E Z HS 81 T-Z HS 82 R HS 82 RC-E HS 82 R-Z HS 82 T HS 82 T-Z HS 86 R HS 86 R-Z HS 86 T HS 86 T-Z HS 87 R HS 87 R-Z HS 87 T HS 87 T-Z