Circular No. 484/50/99-CX I am directed to draw your attention to Board”s Circular No. 284/118/96-CX dated 31.12.96 as modified by Board”s Circular No. 304/20/97-CX dated 18.3.97, whereas instructions were issued, inter-alia, that in case where bonds have to be furnished under rule 13 and 14,