This version of the ZC1 is believed to be an attempt to make the ZC1 more acceptable as the move to common equipment standards gathered momentum. Today it is not clear if these sets were manufactured like this or if they were standard production sets which were modified as a batch after manufacture. Nor is it known how many of this variant were produced.
British High Command saw the ZC1, despite its superior qualities, as outside the range of equipment considered to be standard issue for British and Commonwealth Forces. With a growing trend towards rationalisation of equipment to facilitate joint training, the supply of common spares and the interchange of equipment between different units forming part of joint operation forces, the ZC1 was frowned on. Senior Command believed the 19 Set was standard "Kit".