There wasn't a separate part number for black grips Thunder, it was all the same part number but you got what came. I don't know, but I presume that 'black' was in fact the deepest shade of brown..., the colour of the resin. It's the same as was used ages ago for insulating things electrical!

The grips were still available as spare until the mid 80's as I seem to remember and the Guards Depot at Pirbright, where the bands were based had about 10 bayonets in stock for each bandsman!

Thinking about it, maybe that was the best use for them, the band!