Mark Systems, Inc

NOTE: This is a used surplus item Graded Excellent. Expect finish wear, scratches, dings, etc... (See photos )

Only one is available, the item pictured is what you will receive. Item has been tested and is in working order (See lens demo picture) 

Note: Batteries are dead but must be installed for external power use. Tested with DC Power Supply set to: 13 V / 2.5 A via external power jack (rated 12–28 V). Power on using the button above the jack; Check the built-in battery/power meter on the device to avoid over- or under-voltage and prevent damage.
Press and hold the left-thumb button to activate the auto-stabilizing gyroscope—it auto-engages only with noticeable motion (e.g., on a ship, truck, or plane). 

Description:
The Mark Systems, Inc, Mark 1610 is a professional-grade, originally built for police, military, and government agencies, image-stabilized binocular system with dual eyepieces and a single large-aperture objective lens. Its gyro-prism stabilization ensures a steady view, even at high magnification. The left-hand grip houses all operational controls, including power switches for the binocular and stabilization system, as well as a magnification lever. Additional features include a battery check function, instructional labeling, and soft rubber eyecups to block side glare. The unit stores securely in its original shockproof metal case.

Features
Dual Magnification: 10× or 20× with 50 mm single objective
Gyroscopic Image Stabilization: Powered by 3× 4.5v AA photoelectric batteries or an external power cord (Batteries and Power cord included)
Professional Use: Originally priced and built for police, military, and government agencies
Ergonomic Grip: Left-hand strap with integrated controls for magnification, power, and stabilization
Adjustable Optics: Interpupillary distance, focus knobs, and diopter adjustment (+2 to –4)
Durable Build: Shockproof grey-blue metal case, robust housing, and can be tripod-mounted. 
Optics: Blue-coated lenses for enhanced clarity
Vintage Patent: US Patent 3,473,861 (1969 design by Mark Inc., Cupertino, CA)
Rarity: Our research found the Mark 1610 was made/distributed by Stabilized Optics Corp. (SOC), Sunnyvale, CA. This item is marked Patent Pending Mark System Inc., the designer/patent holder of the Mark 1610. No markings were found for SOC. No info could be found on the total number of units made. On the bottom of this device looks to be a stamped SN: 221, as there is also a label on the case of 221

Specifications
Objective Diameter: 50 mm
Eyepiece Diameter: 42 mm (diopter rings 46 mm; eyecups 67 mm)
Length: 14"
Height: 6.5''
Width: 6.5"
Weight: 5.2 lbs
Mounting options: Tripod socket
Tripod Adapter Disc: Stamped #1164