This kit is awesome, one of the best little upgrades you can do to improve the reliability of your 10/22.
Both parts are EDM cut and hardened, literally the most precise and clean way to cut parts of this sort. The extractor hook is .005" closer to the bolt face for a tighter 'bite' on the rim, and the firing pin is .004" thicker than the factory one to reduce the side to side slop.
After the firing pin is cut and hardened, the striking surface is precision ground to the optimal angle to reduce light primer strikes. They don't release all the science and black magic that they imbue this part with to achieve the results, but there is no question, it makes a significant difference to reliability. I can't tell you the number of guns which have walked into the shop with irregularly firing/cycling issues; we drop this kit in and it's good to go!
(Not always of course, there are other things which cause malfunctions... but there's an above average chance that this kit will cure what ails you)
This does require assembly of course. After you remove the bolt from your firearm, you will need to drive out a pin and manage some little tiny springs and detents to get these parts installed. We are working on getting a video up, but be aware of what you're getting yourself into before you buy this kit.
Thanks for looking!