Requirements for seats and covers (with or without metal components) of two types, both types being suitable for use with WC pans complying with BS 5503 and 5504.Cross References:BS 771:Part 1BS 771:Part 2BS 891:Part 1BS 903:Part A26BS 970:Part 1BS 970:Part 4BS 1004BS 1224BS 1322BS 1449:Part 2BS 1706BS 2782:Part 5:Method 540ABS 2874BS 3382:Part 1BS 3382:Part 2BS 5503:Part 1BS 5504:Part 1BS 5504:Part 2