The original UK release of this single came in a thick card picture sleeve. The artwork on the sleeve is much sharper and the colours are more truer than they appear on the reissue. The back of the sleeve has a circular EMI logo, along with the printed letters G&L along the bottom right-hand corner. The back of the sleeve also has a rectangular opening with angled cuts at the sides.
First issue singles also have the inscription "Remember The Whales" etched into the run off vinyl on Side A. The reissue does not have this inscription.
Kate's earliest first issue releases are more difficult to find these days, and they also tend to be more expensive as a given.
Side Note: For anyone that's interested, G&L stands for Garrod & Lofthouse Ltd. They were one of the biggest sleeve printers in the UK back in the day for vinyl LPs and Singles.