[Yes, Built-In] great product

[19mm f/1.26] great product for both day and especially at night for viewing the stars and satellites moving around. I wifi to my iPad as a monitor while videoing the night sky, works great for panning on the tripod without having to keep the binos in my face. focus is a little touchy but just be gentle. for the price I am extremely happy, and shipping was FAST ! could you suggest a 12 inch portable monitor that is plug and play for these binos ??
overall I am extremely satisfied. I can see so much now that I couldn't before !!!

[1x] It does affect my night vision when I use it, but because its two red LEDs turn on at MINIMUM BRIGHTNESS it does not affect it much. Power and brightness are controlled by a small thumbwheel, like the volume control on a portable radio.
I have another red light but it starts out way too bright. I never use it because of this.
It comes with a 9V battery and seems to have good battery life. It is not water or weather resistant. The lanyard is quite good: simple and functional. I can put it around my neck with plenty of slack.

[17 mm] While I have a red light for a headlight that I have usually used. I find this to be a modest cost tool for night photographic work. It's nice that you can dim the light up and down. It's in my photo bag and will stay there as a useful tool.

[19mm f/1.26] Great flashlights that don't disrupt night vision, perfect to use with setting up a telescope in the dark after your eyes have adjusted. Grabbed a couple of these while they were on sale, and they work as expected. Very happy.

[1x] I'm sure this was intended for darkrooms but I use to get around the house at night. I have to get up a lot earlier than my wife and I don't want to disturb her or the baby. There is clutter on the floor and this light lets me see what I'm stepping on without using a light bright enough to wake them. Got it on deal zone at a fantastic price and mine came with batteries in it. They sleep in peace and I don't step on anything that will inflict pain. Come to think of it I should get one for my sister in law who just had a baby.

[19mm f/1.26] This is a great pair of binoculars! It’s like having a rangefinder,
video camera, still camera, daylight zoom binocular and a night vision binocular – all at once! Just received it a few weeks ago and already tested it during the daytime to watch wildlife and at nighttime to stargaze and this is definitely the one you should buy if you just want one device that can do it all! Built quality is solid. It definitely feels like it’s worth the money you paid for it. Full color mode is great because you can see if the objects in the skies
change temperature and color. Daytime viewing is like having two mini-HDTVs right at your eyes. The colors are really bright and vivid. It has several different and very useful monochrome color viewing modes for nighttime, but just leave it in full color for daytime. Do get a power bank to feed it through USB port, so you won’t have to worry about changing batteries often. I will keep batteries inside as a backup only.  Rangefinder works great, you can leave it in automatic mode, and it will keep measuring distance every few seconds, or choose manual mode and it will only measure when you press the button. It has many features inside. I hope to explore each and every one of them in the coming weeks. So far, I am very happy with this purchase!

[-6 to +2] I keep one in each of my camera bags. Perfect for when I’m shooting at night.

[17 mm] You definitely need a strong red light if you're an astrophotographer. This does it for a very cheap price. I also use it to illuminate myself when i'm taking self portraits for 10+ exposures.

[19mm f/1.26] These are not military grade. But for the price I'm surprised how much detail I can see in the yard and field behind my house. With in a hundred feet I can see cats and racoons in the dark. Your not going to see much beyond this and I did not expect to at this price. The only problem I have is loosing my night vision due to the bright viewing screen. By keeping one eye closed during viewing helps. Cant wait to use them at the cabin. Wont have to light up the woods with a spotlight to see the deer and bear.