The Boston Shaker is a classic bar US, it is composed of two parts: a cup of stainless steel and resistant glass, nothing more.
The principle is simple, you put all the ingredients in the glass (which is otherwise unnecessarily graduated, is not aesthetic and was metered dose for that), added with ice placed over the steel Timballe to seal it and stirred.
In ppratique it's a bit more complicated and I invite you to view some videos on the internet on how to properly seal it, how to keep to agitate and finally how to separate the two pieces then. Do not be scared, the hand is easy to take with a little practice and it is really within the reach of all.
Once your mixture ready simply pour it into a glass filter using a type "Hawthorne" (essential accessory to buy with your shaker).
Regarding the shaker itself is very well done: the matérieaux are quality and the finish is perfect. So it is very pleasant to use and extremely efficient: nothing to do with the shaker 10 you can override such a can steel is so late.
I just love this shaker that I just ordered a second rescue :)