sealing materials sealing cord for metallic threaded joints in contact with 1st 2nd and 3rd family g ases and hot water non hardening jointing compounds conforming to bs specification en 751 2 1997 class ar p compound with dvgw csa nsf ansi 61 as nzs 4020 approval material required in packing of 150 meter s spool warranty period 30 months after the date of delivery