Gallagher & Lyle were Scottish singer-songwriters Benny Gallagher (b 10 June 1945 in Largs) and Graham Lyle (b 11 March 1944 in Bellshill).
These are photos from concerts where Gallagher & Lyle played, so they may be of other bands that played the concert as well.
Supertramp / Gallagher & Lyle Jan 27, 1975 Leicester, England, United Kingdom Uploaded by Prc56