The Royal Navy was quite late in adopting rank slides for its ratings, only introducing them in 1970 to be worn on woolly pullies, and then only for Chief Petty Officers. Leading hands and petty officers were still expected to sew their badges of rate onto their garments, but as the decade went on, it became clear that in order to modernise, shoulder rank slides were needed across a wider set of uniforms and in 1979 new badges were introduced, the older design then being limited to foul weather clothing. The 1970 pattern badges were blue on white, the 1979 pattern changed this to gold on black for CPOs, and red on black for POs and leading hands (LH). Further developments took place in 1995, when all badges became gold on blue. Further patterns were introduced for combat uniforms in subdued colours and the result is a myriad of different slides for the collector to look out for:

Here, left to right, can be seen the orange tab of a recruit undergoing training, 1979 pattern LH, 1970 pattern LH, 1995 pattern LH, black on green LH slide for wear with DPM, Desert DPM LH slide and an AB’s slide in MTP. The slides can be found printed and embroidered depending on when they were manufactured.
As mentioned, it is fun to try and get all the ranks for each particular design, here for desert DPM we have the ranks for AB, LH, PO, CPO and Warrant Officer 1st Class:

The slides themselves were originally issued in small cellophane bags to protect them until they were handed out to the rating:

Most of the slides are plain on the back, the 1970 pattern however have a Vocab number and an NSN number printed on the rear in blue:
