Age: 1320 (season 2)
Unit: 侍ノ弐 Sengoku Astray Gundam

As a Gundam Builder and Operator, Nils employs advanced knowledge and natural skill (most likely gained from his martial artist abilities) along with the expert craftsmanship and tuning of his Sengoku Astray in order to win his battles by using tactical decisions. While he shows no apparent gratification over his victories or concern for the nature of battles themselves, believing them to be a stepping stone in his main goal of advancing his research on the Particles

Seven years later, he is now married to Caroline Yajima, (dropping his surname from Nielsen to Yajima) and is the chief engineer at Nielsen Labs and Yajima Trading. Nils no longer partcipates in championship tournaments, as he feels his extensive knowledge on Plavsky Particles gives him an unfair advantage.
(Source: Gundam Wikia)