S45 speakers actually come in three flavours!
1. S45 Type 6302 - three way speakers of the first Uniphase release. Single grille and resin back. I am not sure but I think they had the option of a trumpet floor stand - but I have never seen a pair with these.
2. S45-2 Type 6312 - as the type number suggests, a development of the original with very similar performance. They can be differentiated by the fact they have a flat back covered in black vinyl. The badge on the front still is just S45 but the type sticker on the back labels them as S45-2. They come with square floor stands.
3. S45 Type 6427 - two way speakers from the revised Uniphase speakers - not related to the previous speakers , probably more a replacement for the S30.