MG 1/100 RGM-79 GM ver. 2.0

It sounds like you're describing the RGM-79 GM Version 2.0 model kit, a significant upgrade from Bandai's 1999 version. This model seems to be a more accurate representation of the Mobile Suit as it appears in the original "Mobile Suit Gundam" anime series from 1979-80.

Known colloquially as "Jim," this Mobile Suit is the Earth Federation's answer to mass-produced warfare, inspired by the RX-78-2 Gundam. The inner framework, intricate details, and articulation offer modelers an enhanced building experience and a more lifelike result. The GM comes with various customization options like optional waist armor and a diverse arsenal of weapons, making it a must-have for fans who enjoy setting up large-scale dioramas or battles against Zeon forces.

The inclusion of a "Gundam Chronicle Battline" promotion card in the first production run is a nice bonus, although it's noted that availability cannot be guaranteed by retailers like HobbyLink Japan.

Given your professional background in digital marketing, especially in creating content for Bandai goods in both traditional Chinese and English, this detailed and feature-rich model kit would offer a great subject for product postings or promotional campaigns on social media platforms like Facebook and Instagram. You could highlight the kit's various features, customization options, and its historical context within the Gundam franchise to attract fans old and new.