Otis TechnologyMC-10 Full Auto Grease Precision Applicator Brush, Multi, one Size

Easy application works great.

I initially had purchased the “regular” MC-10 in the spray bottles, and was immediately annoyed with that installation method. It is extraordinarily hard to lube rails, slides etc without a lot of waste. So, when I noticed this pen I was instantly intrigued, but thought it was weird they called this a ‘grease’ while the spray MC-10 is not.I contacted Otis, and was told it was the same product, so I purchased it hoping it would make MC-10 more usable. It has done that, and I do like the product overall. However, this is absolutely a grease while the other is an invisible liquid. That being said, they seem to work the same way and this ‘grease’ seems to almost dissolve once it sits on the gun, and/or the bolt has been cycled etc.If you are going to use MC-10, this precision applicator is pretty much a necessity along with the spray. I would not pay full price for everything, but if you can snag the spray when it gets discounted it could be worth it. And I’m happy with the purchase overall.I have only put 100 rounds or so through an AR, but I am impressed so far. I am going to install MC-10 on a 9MM handgun and will also continue using it exclusively on one of my AR15’s. My goal is to comeback and update this review to note whether clean up after 1000 rounds or so was any easier, as that is supposed to be an MC-10 benefit.**Note, I paid for this product out of pocket and was not compensated for this review in anyway**UPDATE 3/17/20I gave this a shot for as long as I could. Between August 2019 and March 2020, I put approximately 1800 rounds of 5.56/.223 down range using an AR-15 exclusively cleaned and lubricated with MC-10. Ultimately, I do like it as a lubricant. The spray and grease compliment each other well, and this applicator helps with accurately installing both the spray and the grease. Otis is also correct when they say it gets better with use, and as it works it’s way into the weapon.That being said, my rifle has gotten dirtier and dirtier as more rounds were fired (obviously) and the “cleaner” provided with MC-10 is not strong enough for an even moderately dirty rifle. Not too mention, the amount of cleaner needed to make any impact on the crud and carbon, greatly outpaces the amount of lubricant being used. Leaving you with one product but not the other.It’s quite possible my AR would have kept running without a failure for another 1800+ rounds. However, I just do not maintain my weapons that way. Especially living in humid Texas. With the humid summer coming up, I need to know my guns are cleaned, oiled and protected. Ultimately, I have moved this weapon over to Slip 2000, which is what I tend to use on my AR’s.After prolonged use, I’m moving my review to 3 stars. MC-10’s use as a lubricant stands out, but there are other products on the market more deserving of my money. Especially since MC-10 isn’t meant to be used with other cleaners or lubricants.*******************************I rely heavily on reviews when I make purchases so I put some time into reviewing everything I buy on Amazon for personal or business use so I can help other people considering that item. If you found my review helpful, please consider hitting the "helpful" button below when it asks if the review is helpful!