Keep fog, dew, and condensation from forming on your camera, spotting scope, or telescope lens with this 19.7" Neewer USB FPC Lens Heater for Camera & Telescope Lensesfrom Neewer. The black/purple heating strap wraps around lenses up to 159mm in diameter and warms the glass with power supplied by an integrated 6' cable to a 5V/2A USB-A port. The temperature regulator provides three settings: High Mode (125.6°F), Middle Mode (113°F), and Low Mode (98.6°F). The warmer secures around your lens via touch-fastener.

Prevents Dew, Fog & Condensation    For Lenses up to 159mm Diameter    Low, Middle & High Temperature Control    Integrated 6' Long USB Cable

• FPC (Flexible Printed Circuit) technology provides improved thermal conductivity and efficient heating performance.
• Use with camera, telescope, and scope lenses with a circumference of up to 19.7".
• Lens heater features overheating and overvoltage protection for safety.
• The lens heater bends but must not be folded.

Related Questions and Answers

Q: 1. Does this work with the Sigma Art 135?

A: I have no knowledge if they are proprietary to each lense or not. I bought package deal.

Q: 2. Have Sigma 18-200 older version. Does not autofocus on D5500. Will firmware update solve this?

A: No, you cannot update the older 18-200mm.

Q: 3. Can this be used with the Sigma 10-20 3.5 ?

A: No it cannot. I am unaware of any customizations that can be made to the Sigma 10-20mm 3.5. I do use the USB dock on my sigma 150-600mm sport. It is a useful tool.

Q: 4. Does the Sigma USB Dock work on the older Sigma 120-300 2.8 zoom lenses or just the newer lenses?

A: This dock is only compatible with the Sigma Art, Contemporary, and Sports line lenses featuring a Nikon F lens mount. It is not compatible with the older Sigma 120-300mm f2.8 lens (Sigma model # 136101).

Q: 5. Has anyone used the dock on the Art 14-24 f2.8? If so, did it help or make a difference? I have a D850 and a D500 but only use the lens on the D850.

A: The doc allows firmware updates which may improve certain general or specific performance aspects of the lens. Keeping firmware up to date is recommended.

Q: 6. Do you need to purchase the cord (optional?) in order to gain the Temperature feedback feature of the dew heater ring

A: The Celestron Dew Heater Ring (9.25") BH #CEFHR925 • MFR #94052 comes with a power cord.Simply plug the ring into an external 12 VDC power source for consistent, continuous heat that will prevent dew from forming under even heavy dew conditions. The Dew Heater Ring features two storage clips to keep the power and thermistor jacks secure when not in use while accommodating the telescope's dust cover. Here is a copy of the manual: file://nas-users/pchome/johnp/MyDocs/Downloads/799216.pdf

Q: 7. Can I calibrate my Sigma DG 150-500mm 1:5-6.3 APO HSM lens with this?

A: No, the Sigma USB Dock is only compatible with Sigma Art, Contemporary, and Sports line lenses. This will not work with the Sigma 150-500mm f/5-6.3 APO DG HSM Lens.

Q: 8. Is this necessary for my used Sigma A mount 120-400mm? I have it adapted to my A7RII and noticed some off points while trying to get it to focus on closer subjects while shotting a professional soccer match. Could this be useful?

A: The Sigma USB Dock for Sony A-Mount Lenses will only work with Sigma Global Vision lenses. These are the Art, Sports or Contemporary lenses. Not with the Sigma 120mm-400mm lens that you have, because it was released in 2008, and it doesn't have the connectors for that dock.

Q: 9. Can this dock be used on a mac? I only saw windows.

A: Yes, the Sigma USB Dock for Pentax K-Mount Lenses can be used on MacOS 10.7 or later.

Q: 10. Is this compatible to Sony E Mount's Sigma 18-300mm lens?

A: Thank you for your interest in Sigma product. As of now, Sigma doesn't make a USB dock nor an 18-300mm lens in E_mount. This product is compatible with Sigma SGV lenses for Sony A-mount.