Discovery 925 Series
Voyager 815 & 855
Explorer - 220, 320, 330, 340 & 350
Explorer 360 & 370
Pulsar Headset 590/590e
Voyager 510 & 510s (Headset)
Discovery Series - 610, 640, 645, 655, 665 & 640E
M3000 / M3500
BackBeat 903/906 Headset
The two digit Date Code on this headset is located on the left side, which also has the Power on/off switch. Look at the inside surface (facing your ear) and you will see a printed "CE". Above the CE are four lines of very small print and the third line has "IE XX IC:457A-BB903". The "XX" is the Date Code which is a letter and a number, for example B4 or J9.
BackBeat 906 3.5mm Audio adapter
The two digit Date Code on audio adapter is located on the back of the adapter, and you will see a printed "CE". left of the CE are five lines of very small print and the fourth line has "XX XX ". The second "XX" is the Date Code which is a letter and a number, for example B4 or J9.