This sd gundam papercraft is designed by keikeifactory. MSN-00100 (MSN-100, MSN-001) Hyaku Shiki is a prototype attack use Mobile Suit from the Universal Century timeline. The unit was featured in Mobile Suit Zeta Gundam and Mobile Suit Gundam ZZ and was primarily piloted by Quattro Bajeena (Zeta) and Beecha Oleg (ZZ).
For more information and instruction please visit the author's blog here.
You can download this gundam papercraft from here: SD MSN-00100 Hyaku Shiki Gundam Papercraft free download