Blanco Brand white shoe cleaner in original box, c.1930s-50s

A "Blanco" Brand White Cleaner block ("Keeps White Shoes White"), c.1930s-50s, by Joseph Pickering & Sons Ltd, Sheffield, in its original box.  The box, which measures approximately 7 x 6.9 x 2.8cm (2.75 x 2.7 x 1.1in), has a small tear to the back together with some creasing, marking and general age wear; the block itself is somewhat cracked and chipped around the edges.