Bluetooth Communication, you can find it at your friendly PROTOS Integral retailer - in Rotorua you can visit the team at Lakeland Chainsaws & Mowers or... | By PROTOS Integral - New Zealand | Facebook
Protos Integral Arborist Helmet for Chainsaw Work at Height with Crash Protection
How to Adjust your Pfanner Protos Helmet - TreeStuff.com - YouTube