fitted arm and collar protection. Mk 3 Improvements to the armour included the addition of a more robust right hand shoulder assembly and a non-slip shoulder pad for improved aiming of weapon systems. An Mk 3 A version was issued with studs on the plate pockets to better secure the hard armour plates and retaining straps over the side panels to reduce instances of the velcro opening when under stress. This had been mitigated in earlier vests by the use of a bungee cord around the armour, hooked to the PALS webbing. The vest was mostly produced in Desert Disruptive Pattern Material camouflage, though versions in an experimental multi-terrain version of Disruptive Pattern Material developed during PECOC were also fielded and limited production was undertaken of a version in regular Disruptive Pattern Material. Mk 4 Developed by June 2009 and introduced in April 2010, Osprey Assault Mk 4 body armour (later simplified to Osprey Mk 4 body armour) was made available in Desert Disruptive Pattern Material camouflage, a solid tan colour, and the new Multi-Terrain camouflage, though an olive version was demonstrated in 2010 and CQC offers a closely related 'Rhino' body armour set in regular Disruptive Pattern Material camouflage. Modifications were made to the velcro coverage to improve fastening security and soldiers were given a choice between an OPS panel with adjustable T Bar fittings and a pair of cummerbunds fitted with adjustable front webbing straps and featuring pockets for side hard armour plates. Finally, the most striking change when compared to previous iterations is that the front and rear hard armour plates are now carried internally rather than in an external pocket; combined with the plates being made thinner without reducing effectiveness, this means that the Mk 4 vest provides the same ballistic protection as earlier Osprey vests while being more comfortable to wear, closer fitting, and easier to move in. A ribbed material lining on the inside of the vest improves breathability in hotter climates such as that of Afghanistan. The Mk 4 vest has a higher number of webbing loops and the pouch assortment was increased to twenty-three, with additions including a "commander's pouch" for holding stationery and open SA80 magazine pouches with elastic draw-cords for easier access to ammunition. A modified version of the Mk 4, known as the Mk 4A, eliminated the outer cummerbund and replaced it with pouches for carrying the side armour