Plenty of prime Upsetters here.

Aka the Clem Bushay All Stars, including Candy McKenzie, Dennis Bovell, Janet Kay, Jimmy Mack, Junior English, Moon Rocks and Zabandis…
From 1977.

Tougher-than-tough instrumental by the Links house-band, featuring Joe White and Ken Boothe on keys, and killer guitar and trombone by Harris Seaton and Derrick Hinds. Same circle of heaven as tunes like Sidewalk Doctor and Tight Spot. Something new, ushering rocksteady out the door, into the past.

Two goes, both brilliant, featuring ace trombone. The first take carries the swing, with its wailing, soul-jazz organ more to the fore.

Top-notch, super-soulful rocksteady.
With an alternate take.

Jackie Bernard leading a thumping, yearning overture; backed with The Valentines’ classic Blam Blam Fever. Top-notch rock steady.