‘Pimples’ were a design of anti tank obstacle that could be either fixed into the ground or dragged into place to delay the movement of vehicles, including tanks.
They can still be found throughout Britain, as the were deployed in large numbers in preparation for the threatened invasion, ‘Operation Sealion’.
Dimensions (of an individual ‘Pimple’):
Width 15mm, Depth 15mm, Height 17mm. (All dimensions are approximate)