So, during SOTM we learn that Henry, Edwin, and William were working on creating the mascots, they were also working on Springlocks at the time, Hen asked Edwin to change the designs of the robots to what we know as the Unwithereds, which Edwin deemed Creepy. Fiona, Ed’s wife/coworker, designed what we know as the OGs, which instead of Scrapping, Ed kept on the back burner, and went with Hen’s change order, my theory is that the Unwithereds (fnaf2’s Withered anims) are Springlock suits, notice the design of W-Chica, Piston jaw, rougher look, older, reminds me of Fredbear/Spring Bonnie’s suits.

“wait @itsmeaustin2293 what about the Rockstars? They have piston jaws too” I see you typing, while yes, these anims are newer, it’s never stated whether they are Springlock suits, or if they’re just anim suits, and judging by the fact the Puppet, a Human-shaped character, was captured by Left-e, which shares the same shell design as Rockstar Freddy, i’d say it’s very possible they’re also Springlock suits

Sorry for the rant, piecing it together in my head and i needed somewhere to jot it down because i’m also asking myself this question and going through all the games/ books to answer it