From publisher blurb:
This new supplement for 2300AD expands the roles of combat walkers, hard suits and battlesuits, introducing new designs ready to take to the stars. Battlesuits are clam-shell-style unpowered armour (sometimes with assistive exoskeletons), while hard suits are humanoid suits of powered combat armour with enhanced capabilities. Combat walkers are the large but lightweight, non-humanoid walking vehicles.
Also included is a complete and expanded design system for all three, allowing referees and players to create their own designs, from basic utility models to hardened battle machines dedicated to annihilating the growing menaces Mankind is discovering on the far reaches of the exploratory Arms.