Cylindrical canister, labelled Pack/ No 1 Detector Powder/ Mk 1/ Instructions/ Sprinkle a thin layer of/ powder over suspected/ surface. The Appearance/ of a distinct colour/ denotes presence of/ liquid war gas/ Nerve gases give yellow/ or orange colours/ Blister gases give reddish or purple colours/ Non-poinonous/ 11/53 2/54/ MB5 B P D Co/ PR 4 GA.. Lid set inside cylinder, to be levered open. Instructions in black on yellow beige background. Contents intact