Arian 
The Valve Index is a virtual reality headset manufactured by Valve. It was released in April 2019, following an announcement in April 2019. It is the company’s 1st VR headset release.
– This headset requires a connection to a PC in order to be used.
– This headset is heavy. 809 g
– This headset has a high refresh rate. 144 Hz
– This headset has a high horizontal field of view. 108°
– This headset requires external base stations for full tracking capability.
– This headset can be purchased with two 6DoF controllers.
The Valve index was the first headset to be produced solely by Valve, as opposed to the HTC Vive, which was produced as a collaboration between Valve and HTC.
The headset features controllers equipped with full individual finger tracking, that can be held with an open hand due to straps that wrap around the user’s knuckles.
Source: https://www.vr-compare.com/headset/valveindex
