supply of manufacture and supply of hvn-66 insulating liner conforming to rdso drg no t-8992 alt- 2 for use on sharp curves with wider psc sleeper t-8979 to t-8982 suitable for 60kg (uic)/60e1 rails. this is a safety item. specification: irs specification for glass filled nylon-66/ high viscous nylon-66 insulating liners sl. no t-44-2025 (third revision). , manufacture and supply of hvn-66 insulating liner conforming to rdso drg no t-8992 alt 2 for use on sharp curves with wider psc sleeper t-8979 to t-8982 suitable for 60kg (uic)/60e1 rails. th is is a safety item. specification: irs specification for glass filled nylon-66/ high viscous nylon-66 insula ing liners sl. no t-44-2025 (third revision). [ warranty period: 30 months after the date of delivery ] ]