An exercise apparatus used by an individual that is performing a variation of a push-up exercise. Processing of the flakes include softening the surface of the flakes, embedding a surface treatment material into the softened surface of the flakes, and either supplying the flake as loose ground cover, or compressing the flakes into a portable mat. Protective instructions are inserted into the program instructions. The sleeve comprises a plug cap for receiving the plug. As the slotted sleeve is brought against the rounded closed end, its slot is opened and travels open towards the open end where the cables are. The density of the end explosive product may be varied according to the gas flow and this is controlled before introducing the explosive into the bore.