A lot of bands like Fleetwood Mac, Ten Years After, Savoy Brown and others started out mainly playing the blues but on later releases these bands brought in other elements such as psych, jazz, and prog but still mainly focusing on the blues.
One such band was the Climax Blues Band with thier release Tightly Knit from 1971. Led by one of the most under rated guitarist Pete Haycock. A magician on the slide giutar.