You can determine pipe size byusing the sizing guides at the bottom of this page (a sizing chartis shownatthetopofeachpipeandpipefittingpage).However,forthemost accurate sizing, use a sizing gauge or kit (sold separately at right).Most straight (parallel) threads are measured the same way astapered threads.
The first Head of Ravenclaw House was the famous co-founder of Hogwarts, Rowena Ravenclaw, and the only other known Head of House was Filius Flitwick. As no Ravenclaw students are known to have returned to Hogwarts to teach, it is unknown who the next Head of House will be. 1  Rowena Ravenclaw - One of the four Hogwarts founders and founder of the Ravenclaw House.  Filius Flitwick - Head of Ravenclaw during Harry Potter's time at Hogwarts.
There are a lot of theories surrounding the identity of the Three-Eyed Raven, and the character's final words to Bran (It's time for you to become me) have only fueled some of these. It has been suggested that Bran will go back in time and train up the Raven, who will in turn train up Bran in a continual time-loop.