’A critical feature of the hand-held device is the cup that holds the bird's head in exactly the right place for the spike to be delivered accurately between the first neck vertebra and the base of the skull.’

’The action allows, with very little pressure, sufficient penetration to sever the spinal cord close to the brain itself. Because of the precision with which the spike is placed, one closure is sufficient to render the bird immediately unconscious, with death following seconds later.’

John Dalton BVMS MRCVS