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.
The Ravenclaw common room is in one of the castle's towers and is wide and circular. You have to climb a tight spiral staircase to get there. It has graceful arched windows, and the walls are hung with blue and bronze silks. The domed ceiling is painted with stars, which are echoed in the midnight-blue carpet.