I have a set of Peltor Tactical XP ear defenders for sale. They cost me £230 new, been used a few times, in excellent condition.
Level dependent function that lets you hear ambient sound: conversation, machine sounds and warning signals
Ghost voice guided menu system
Equipped the following functions: volume for the level dependent function, balance, adjustable release time, equalizer, volume for external input and input mode
Plenty of space for the ear
Last setting is stored when switched off
Automatic shut-off after two hours if no function is used
Warning signal when power is low, before shut-off
£100 including postage.
PM for for details