The Sennheiser IE PRO BT Connector is a smart piece of kit for those wishing for wireless connection when using the IE 100 PRO Monitoring Headphones. It is essentially a light-weight semi-wireless connector cable with a built-in microphone and remote for making calls and controlling sound levels. Support from aptX Low Latency ensures that the sound you are hearing is perfectly synchronised to video, whilst a full charge provides you with 10 hours of battery life. The Bluetooth connection is reliable, with the cable resting comfortably behind your head via reinforced ear hooks. You can use the IE PRO BT Connector with the IE 100 PRO, IE 400 PRO, and IE 500 PRO in-ear monitors - however, they are not compatible with the IE40 PRO as these utilise a different connector. This is the same BT cable that comes equipped with the Sennheiser IE 100 PRO Wireless Professional In-Ear Monitoring Headphones.