"Lenny" is the tenth and final track on the first Stevie Ray Vaughan and Double Trouble album Texas Flood.
[1] The song is in 4/4 time and notated in the key of E flat major (but instruments are tuned down a half-step, so the chordal structure is in E).
It is played very slowly and freely, with Vaughan alternating between jazz-inflected chords and solo runs.
Its style is influenced by Jimi Hendrix ballads like "The Wind Cries Mary".
[2] The song was written and named for Vaughan's wife at the time, Lenora.