Good picture of a British pick and helve made in 1943 by Hardypick Limited, Sheffield (part of the kit of a Daimler Dingo in the USA).
It clearly shows the shank is about half as high (deep) as on the US one, therefore the British helve has a metal reinforcement for stability of the pick head.
Thus far, I have only seen the US type fitted on / supplied with CMP trucks.
