Thermal scopes / FLIRDiscontinued
FLIR Zeus Pro 640 4-32x100
640×512 · 17 µm · 100 mm · 7 h · Discontinued
An Armasight design, sold under the FLIR name after FLIR bought Armasight on June 28, 2016.
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Coyote at 100 yd
36 px tall at the shoulder
Coyote at 200 yd
18 px tall at the shoulder
Coyote at 300 yd
12 px tall at the shoulder
Identify a coyote out to
Identification distance
Our estimate of how far away you can tell a coyote from a fox or a dog. It is calculated from the lens and sensor, assuming good conditions.
~300 yd
Farther than 95% of the 208 current thermal scopes we track (#11).
Ground across the screen at 100 yd
Field width
How many feet of ground fill the screen at 100 yards. Wider makes scanning faster; narrower usually means more detail on the animal.
33 ft
Wider than 5% of the 208 current thermal scopes we track (tied for #193).
Specs
| Sensor | |
|---|---|
| Resolution Sensor resolution How many heat-reading pixels the sensor has, such as 384 × 288 or 640 × 512. More pixels show more detail, but the lens matters just as much. | 640 × 512 |
| Pixel pitch Pixel pitch The size of each sensor pixel, in microns. Smaller pixels mean more magnification from the same lens. Most current thermals use 12 microns. | 17 µm |
| NETD (maker’s claim) NETD (thermal sensitivity) How small a temperature difference the sensor can show. Lower is better, but brands measure it differently, so numbers from two makers are not a fair comparison. | — |
| Refresh rate Refresh rate How many times per second the picture updates. 50 or 60 times a second looks smooth; lower rates stutter when you pan or a coyote runs. | Not published |
| Optics | |
| Lens Focal length The lens number in millimeters, like 35 mm or 50 mm. A longer lens puts more pixels on a distant animal but shows a narrower slice of ground. | 100 mm f/1.4 |
| Base magnification Base magnification How much bigger things look before any digital zoom, like 2× or 4×. Higher is not automatically better: it narrows your view. | 4× |
| Max digital zoom Digital zoom Electronic enlarging of the picture. It makes the animal look bigger but adds no detail; past about 2× to 4× the image gets blocky. | 32× |
| Field of view Field of view How wide a view you get, in degrees. A wide view makes scanning for animals faster; a narrow one usually means more magnification. | 6.2° × 5° |
| Detection range (maker’s claim) Detection range The maker's figure for how far away a warm object shows up as a dot or two. It is far longer than the distance you can tell what the animal is. | — |
| Display | |
| Display Display resolution How many pixels the small screen inside the eyepiece has. A sharp screen looks cleaner but cannot add detail the sensor did not capture. | Not published |
| Power | |
| Battery | 4x CR123A or 4x AA, removable |
| Runtime Battery life (runtime) How many hours the device runs on a charge, by the maker's test. Real runtime is shorter in the cold and with Wi-Fi, recording or the rangefinder on. | 7 h |
| Features | |
| Rangefinder Laser rangefinder A built-in laser that measures how far away the animal is. The rated range is for big, reflective targets; expect much less on a coyote. | No |
| Storage Onboard recording (storage) Built-in memory that records photos and video of what you see. Useful for reviewing shots and sharing hunts; listed in gigabytes. | — |
| Wi-Fi / app Wi-Fi and app A wireless link to a phone app for live viewing, downloading videos, changing settings and updating the device's software. | — |
| Riflescope | |
| Eye relief Eye relief How far your eye sits behind the eyepiece and still sees the full picture. On a rifle scope, more distance keeps the scope off your face under recoil. | — |
| Recoil rating Recoil rating How much rifle recoil the maker says the scope can take and still work and hold zero. Makers state it in different units, so compare carefully. | — |
| Mount Mount How the scope attaches to the rifle: standard rings or a rail clamp, fixed or quick-detach. A good mount does more to hold zero than anything else. | Picatinny rail |
| Ballistic calculator Ballistic calculator Software in the scope that moves the aiming point for distance, using your bullet's data and the range to the animal. | — |
| Zero profiles Zero profiles Saved sight settings for different rifles or loads. Switch profiles instead of re-zeroing when you move the scope or change ammunition. | — |
| Build | |
| Weight Weight How heavy the device is. Check whether the maker weighed it with or without the battery, because brands do it differently. | 45.9 oz |
| Water rating IP rating (water rating) A two-part code for how well the device keeps out dust and water. IP67 means dust-tight and survives a short dunk; an X means not tested. | Not rated |
| Operating temp Operating temperature The temperature range the maker says the device will work in. Batteries lose much of their runtime well before the low end of that range. | -4°F to 122°F |
| Buying | |
| Warranty Warranty How long the maker promises to repair or replace a faulty unit. Check whether it needs registration and whether it passes to a second owner. | 2 years standard, 3 years with product registration, 10 years on the detector |
| US price US price The price we found for the unit in the US, with where it came from and when. Prices change often, so treat it as a snapshot. | Discontinued |
| MSRP MSRP The maker's suggested retail price in the US: the list price, before any sale. Useful for seeing how good a deal really is. | Not published for USNo list price found on flir.com; Wayback captures of the product page were not checked for a price in this pass |
Source: FLIR Zeus PRO 640 4-32x100 datasheet (PDF, updated 11/22/2018), FLIR Zeus Pro product page (Legacy Riflescopes, marked Discontinued), FLIR Outdoor and Tactical Systems 2-3-10 limited warranty (PDF), FLIR Systems press release, "FLIR Systems Acquires Armasight, Inc. for $41 Million" (June 28, 2016).
Added October 11, 2026 · Specs last checked October 11, 2026
Current models to compare
In production now, nearest in resolution and range.
- ATN ThOR 5 640 5-40x$3,695
640×480 · ID ~315 yd · 31 ft wide at 100 yd
Compare with the Zeus Pro 640 4-32x100 → - ATN ThOR 5 LRF 640 5-40x$3,995
640×480 · ID ~315 yd · 31 ft wide at 100 yd · rangefinder
Compare with the Zeus Pro 640 4-32x100 → - AGM Secutor LRF 75-640$6,495
640×512 · ID ~320 yd · 31 ft wide at 100 yd · rangefinder
Compare with the Zeus Pro 640 4-32x100 → ID ~320 yd · 31 ft wide at 100 yd
Compare with the Zeus Pro 640 4-32x100 →
Other FLIR Zeus Pro models
Other sizes and versions in the same line.
- FLIR Zeus Pro 336 4-16x50Discontinued
336×256 · ID ~150 yd · 34 ft wide at 100 yd · discontinued
Compare with the Zeus Pro 640 4-32x100 → - FLIR Zeus Pro 336 8-32x100Discontinued
336×256 · ID ~300 yd · 17 ft wide at 100 yd · discontinued
Compare with the Zeus Pro 640 4-32x100 → - FLIR Zeus Pro 640 2-16x50Discontinued
640×512 · ID ~150 yd · 65 ft wide at 100 yd · discontinued
Compare with the Zeus Pro 640 4-32x100 →