 In this video we will show you how to grease your joints. For this video demonstration purpose you will need a male joint, a female joint and some grease. If you want to connect a male joint and a female joint without greasing you will hear that it makes noise and sometimes it will even be so stuck that you can't get them apart from each other anymore and when doing things on a vacuum air will leak through the joint. To prevent this from happening we will add a tiny bit of grease. You can add a tiny bit of grease at the top part of the male connector, place the female joint over it and rotate it. You should see a slight change in opacity around this area of your joint. This is how you properly grease the joint. What you can also do is put grease all over your joints and then when you connect them and rotate them you will see that the grease goes everywhere. It will also go on the inside of your flask, it will come out on the top side of the flask and everything on the inside of your flask will probably end up in your product giving you a higher yield but less pure and you can actually see this on NMR. So if you have joints that are fully greased you can clean them with a bit of tissue and even if it's really bad you can clean them with a bit of tissue and some pentane and then the grease should dissolve in the pentane. This is how you grease your joints.