supply of manufacture and supply of hvn-66 insulating liner conforming to rdso drg. no t-8791 & t-8792 alt-3 for use on sharp curves.manufacture and supply of hvn-66 insulating liner conforming to rdso drg. no t-8791 & t-8792 alt-3 for use on sharp curves.,manufacture and supply of hvn-66 insulating liner conforming to rdso drg. no t-879 1 & t-8792 alt-3 for use on sharp curves with wider psc sleeper t-8621 to t-8624 suitable for 60kg ( uic)/60e1 rails. this is a safety item. each set of hvn liner consists of one hvn liner to drg. no. t-8 791 and one hvn liner to drg. no. t-8792. specification: irs specification for glass filled nylon-66/ high viscous nylon-66 insulating liners sl. no t-44-2025 (third revision). [ warranty period: 30 mo nths after the date of delivery ] ]