Eyepiece 44-49mm & Objective lens 30-35mm

These caps are 1000% more robust then a butler creek scoop cap. the build quality is amazing. I was only going to give this a 4 star but i changed my mind while writing this. my issue is really more of a pet peeve than anything. this cap has a rubber boot that holds it to the diopter (which is a really good idea as it really holds on). when trying to rotate the diopter the rubber torques but not the diopter since the rubber is holding the more of the tube then the diopter ring. so when rotating it the cap come off the end of the diopter a bit. it does snap back when you let go. you just have to make more of an effort to rotate the diopter then on say a butler creek

Once the optic was installed on my rifle, these easily slid on and stay on. They are easy to open and close and haven't popped open on their own when I didn't want them to.It isn't really a negative, but two notes from my experience:1.) If you will be shooting with others or sometimes wear glasses and sometimes don't, adjusting the optic focus ring is annoying with these on. You have to remove the flip it, make your adjustment, then reinstall. Once you dial your optic in if you're not sharing a rifle or have variable vision situations like glasses / no glasses this won't impact you.2.) There is a mechanical first stop on the flip it that faces you so it stops at 180 degrees (straight up) instead of 270 degrees (laying on top of the optic). I don't understand why you would want the 180 stop, and the front cover does not have this. The first time I used them I didn't realize you could push past the 180 degrees and didn't want to force it, so it kept hitting the bill of my hat when I would shoot. This is not an issue now that I've discovered you can simply snap it to the next setting and it will be out of the way but is a weird design IMO.Overall they are easy to install and use, do their job, and look cool. Five stars in my book.

Just as described, quick shipping

Good product...objective is solid and tight. Ocular cap is loose and slides when opening...they close securely so may loosen up some. I have removed and cleaned it and ocular surface with alcohol to remove any film or dust...to see if would get more secure. Still working...might rough it up some on inside of rubber sleeve or try to clean with acetone to see if better surface contact. Otherwise are outstanding in function and ability to seal.

These are the best scope caps out there, the rubber Gromit really keeps everything in its place

They fit my scope perfectly and work as intended. Work just as good as the high dollar ones, that being said I can remember when other brands were cheaper when they started off. Can’t go wrong.

Quality product , works well. would buy again.

limited to one handgun and one longarm with this kit. the long is a springfield national match m1. went with a nikon monarch 50mm M reticle from a warehouse of NOS to pick from. amazing how crisp good glass from '90's and '00's can be. messed with all the different snap seals out there. paying $100 plus for $5.00 worth of recycled canadian hdpe for snap seals is bs. guess it's fine when using opm, but it better be better than just ok. Arken has done this right. subtle. right durometer elastomeric for job. the injection molding between parts is flawless. if the canadian caps are worth $100, then Arken's are worth $250. use a very very small amount of danco 88693 silicone grease and massage into aluminum THEN wipe down and get your finger friendly with the outer lip of the rubber to foreigner four. then gently slip it home. makes perfect waterproof seal. engineering and execution. nice job Arken.