Weston standard cell type D-402-A serial no.154508, by Muirhead and Co. Ltd. Weston standard cell type D-402-A serial no.154508 1950
Weston standard cell (cadmium cell) marked ICST R.C.S. Phys. Lab. 1383 Weston standard cell 1900-1949
Weston standard cell type D-550-A, serial no.310439, by Muirhead Weston standard cell type D-550-A 1960
Weston standard cell (cadmium cell) serial no. 11490 by Griffin & Tatlock Limited, London Weston standard cell (cadmium cell) serial no. 11490 by Griffin & Tatlock Limited 1926-1954