The Puma was DB08 - I'm not sure if that meant it was 'development batch no. 8' or not. Seems logical. Became rather non-standard, especially regards the blades. Remained metal to the end. Good for fitting pressure sensors and strain gauges.
241 was actually a world-class piece of kit, and as an experimental vehicle for basic research, well ahead of its time even towards the end of its working life. It had the usual range of aerodynamic and inertial sensors, plus with each blade hinge instrumented to record flap, lag and feather. Research blades measured pressure and strain. There was even an instrumented tail rotor blade.
Fabulous stuff. Never really warmed to the Lynx that replaced it (ZD559)