Well, Gene, Peter, Paul are the original members. Ace Freely, ( the spaceman ) was replaced by Tommy Thayer. Who, used to be in the band Black-n-Blue.

In the past, other guitarists who had taken Ace's spot wore different costumes than ace and had their own identity. However, I guess they wanted Tommy to take on the identity of the spaceman. So, he wears Ace's old costume. Or a new one made for him.