Avantree Quartet-Extra - 2.4G RF Wireless Add-On Headphones Quartet Multiple Listening System, Scalable to 100

[ONLY WORKS WITH QUARTET] This single pair of 2.4G wireless headphones is an add-on for the Avantree Quartet bundle (sold separately). Add up to 100 of these headphones to the Quartet bundle and enjoy an outdoor movie or silent concert without disturbing the neighbors.
[LESS DELAYS, BETTER QUALITY] The Quartet-Extra headphones feature 2.4G technology and NOT Bluetooth. This reduces the audio lag down to ~30ms -- significantly less than the 220ms of standard Bluetooth and even the 40ms of aptX Low Latency. This also improves overall sound quality due to 2.4G ' s higher bit rate & extended bandwidth.
[INDIVIDUAL VOLUME CONTROL] Each pair of wireless headphones are equipped with built-in individual volume controls, so everyone can listen at their own desired volume.
[LIGHTWEIGHT & COMFORTABLE] These headphones are ergonomically designed to be lightweight and flexible, featuring soft memory foam earpads and an adjustable headband. Enjoy all-day, pressure-free use.
NOTE: Replaceable earpads are available for purchase.
[EXTENDED PLAYTIME] With a battery life of up to 20 hours, these headphones will last through your longest movie or concert sessions with time to spare.