G-Shock metal covered GM-110 series is the GSHOCK rainbow GA-110RB-2ADR model, which has a unique gold and rainbow dial. On other models with rainbows covering entire bezels such as GWF-1000BRT-1A or MTG- BVLM-4A ,the right side of the bezel features traditional red colors while on left there are orange ones and in the middle rainbow IP in order to match its sibling watches face design for better readability when checking time but also create contrast between them visually speaking .The two sides differ significantly in terms their materials used; each one getting different treatment like carbon fiber versus stainless steel (gold).
In Japan G-Shock Rainbow color GA-110RB-2ADR is not a limited edition and price is 32000 JPY excluding VAT and the price in US will be $280. Gshock rainbow IP GA-110RB expected to be released in other Asian countries and probably worldwide.