You can readily determine that it’s a High Grade kit because it will have the abbreviations “HG” on the box and its box art is in landscape format. As for the 1/100 Scale High Grade kits, you won’t be seeing any HG letters on the box, though you’ll know it’s a 1/100 HG kit if it doesn’t have “MG” or “Master Grade” printed on the box art, and the box art is usually in portrait format. Don’t get confused between 1/100 HG and 1/100 MG kits! First timers might get confused because they looks the same.
With regards to detail, HG kits already look great when built straight from the box without any painting. They have a moderate amount of parts to assemble. Adding some panel lining will boost the detail and appearance of your High Grade kit as well as some minor painting in some areas. High Grade kits include some foil stickers for added detail of your model and sometimes the kit also includes some clear stickers as the model’s decals. The ability to pose models has been improved through the years. In older High Grade models during the 90s, the articulation HG kits were limited but satisfactory, but in recent years, Gunpla technology has advanced a lot and articulation of newer HG kits are superb to the point of being comparable or equal to that of Master Grade kits!
High Grade kits are suitable for everyone, and it’s usually where first time Gunpla hobbyists start their Gunpla modeling journey. Master Grade Now if you want more detail, mechanics and an inner frame skeleton to show off, then Master Grade kits are for you! They are the next level up from HG kits, and while more expensive, the pay-off is worth it due to the kits’ level of detail, included gimmicks, mechanics and some dry rub decals that will greatly improve the awesomeness of your model. Master Grade kits only have the 1/100 scale which are usually around 18 cm tall.