We're an AR & VR developer selling no longer in use equipment like this developer edition Acer VR Mixed Reality Headset (only) no controller. 

Acer's MR headset lets you blend physical and virtual worlds. A hybrid of both Augmented Reality (AR) and Virtual Reality (VR). Acer's Windows Mixed Reality Headset is designed for comfort, freedom of movement and to unite cutting-edge technology with futuristic practicality to maximize your computing experience. 

Specs

• Display Size: 2.89” x 2
• Resolution: 2,880 x 1,440 (1,440 x 1,440 per eye)
• Refresh Rate: 90Hz - Using HDMI 2.0, 60Hz - Using HDMI 1.4
• Tracking Sensors: Gyroscope, Accelerometer & Magnetometer
• Tracking Camera: Inside Out B+W VGA camera
• Connectivity: 1 x HDMI 1.4/2.0 & 1 x USB 3.0 (Cable Length: 13 feet)
• Includes: Headset & Cable
• Field of View: 100°
• Maximum Interpupillary Distance: 2.48"
• Pixel Density :706 ppi

Batteries Required; 2 AA (not included)

Dimensions:  2.9"H x 7.7"W x 4.3"H

Weight (Approximate): 1.87 lb

Interfaces/Ports: Audio Line Out, HDMI 2.0. MI Version, USB