Kat Ryan is a character who appears in the 2000 Max Steel series since its second season.
Shortly after Rachel is promoted, Kat, another N-Tek agent, becomes Max's new partner. At first they don't get along, but after Jefferson Smith makes them work together, they develop some mutual respect. Having near the same age as Josh and Roberto, she has a sister-like relationship with both kids, just like they see each other as brothers. Kat's surname was unknown at first, but it was revealed in one of the last episodes, just like the fact that she was in a street gang when younger.
Kat also played extreme sports, but she left it to become an N-Tek agent full-time.
Kat stops appearing in the post-series movies from 2009 onwards.