Plantronics M20 - Manual (Page 6)

SPECIFICATIONS
Talk Time Up to 11 hours
Standby Time Up to 16 days
Operating Distance (Range) Up to 33 feet (10 meters), Class II
Headset Weight 11.5 grams
Charge Connector Micro USB charging
Battery Type Rechargeable non-replaceable lithium ion polymer
Charge Time (Maximum) 2 hours for full
Power Requirements 5V DC – 180mA
Bluetooth Version Bluetooth v3.0
Bluetooth Profiles Hands-Free (HFP) Profile 1.5 and Headset (HSP) Profile 1.1
(M50: Advanced Audio Distribution Profile A2DP)
Operating Temperature 32°F - 104°F (0 - 40°C)
Storage Temperature 32°F - 104°F (0 - 40°C)
Charging Temperature 32°F - 104°F (0 - 40°C)