The No4 Mk3 was in fact a general issue bayonet and there were still thousands upon thousands in service in the 60's when the No4's were withdrawn from front line service. I still saw plenty of them in Cadet Force stores and Armouries in the mid to late 80's when their No4's were being withdrawn although by this time many/most were relegated to DP standard. But none the less, still in service. I oversaw the withdrawal of them and kept a few for myself which I kept.