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The binocular shell is made of environmentally friendly, odorless rubber material. The surface of the binoculars is nicely matted and effectively prevents slipping. 

(1)Please check to make sure you have installed 1.5V 6*AA battery. Do not use inferior batteries as their voltage is lower than 1.5V. (We recommend brands like Energizer, Duracell, AmazonBasics, etc.). (2)Make sure the polarity is correct and the contact with the spring is normal. (3)Press and hold the power button for at least 3 seconds to power on. (4)If it still cannot be turned on after 1-3 steps, please try to use a power bank. 

Don’t forget that it’s a manual lens adapter. Works with full manual lenses. If your lens has no physical aperture ring, you cannot control it from your camera 

Any lens that use the M42 size screw in mount. The only other screw mount is M39 and these won’t fit, they would need a different adaptor. They will invariably be vintage lenses and you will only be able to use them in the aperture priority or manual modes, stopping town the iris when metering. Search on EBay for “M42 lens”, that will give you an idea of what you can find.