The Magnetic tape collection.

(from left to right…)

Cambridge Computer Services tape number 10000002 meaning it was almost certainly the second (2400ft) tape to be written to after the ICT 1903 was installed in 1966.  (Early tapes were available in 2400ft, 1200ft, and 600ft sizes and most could be recorded at 600 bpi)

A Pericomp Beginning of Tape (BOT) guillotine. The tape leaders got very creased and frayed in constant use and this device (or a pair of scissors) tidied them up (until you ran out of leader).

Write Permit Rings (available in many colours) WPRs were inserted into the back of the tape spool to allow writing or removed to prevent overwriting. (the source of many a tape reload or rerun)  If you think about it you only needed one ring per deck, maybe 4 and a couple of spares, but because every tape was supplied with one computer rooms tended to be littered with them.

A later ICL 600ft (Tupperware) mag.tape. The Tupperware nickname came from the semi-opaque plastic case they were supplied in to make transit safer.

 Kindly donated by Dave Joyner