Yes, this looks exactly like a YTS-21 tenor, the key giveaway being the one-piece bell key guard covering low C, C#, B, and Bb bell keys. The wide football-shaped side F# key is also a good clue, and the low D key has a pad which barely covers the tone hole. This is a Yamaha YTS-21 stencil, early 1970's era.
Sax Magic
Sax Magic