Kotobukiya M.S.G MH019R Weapon Unit Freestyle Shield
Most of these MSG sets are for offense, but this is for defense! The Freestyle Shield set comes with various plates that allow for multiple configurations and sizes, so you can equip your kits in any way you'd like! All attachments use a 3mm peg, so it's all compatible with every other Frame Arms unit!
Whilst no scale is given it could be used with 1/144 or 1/100 scales quite successfully.