Load of cobblers that is - all you need is one 'Hox' spring. Buy me a pint an' i'll tell you about the time a mate of mine had a rabbit a two 'undred yards wiv a gun that ad one of them in it - and that shot was confirmed by another mate of mine that used to be in the SAS but they kicked him out 'cos 'e was just too hard see...

etc.