I received 2 flutes bought at Steirisches-Volksliedwerk, the "large" and the "small" models.
The large model is rather built on the same technical specifications than the small one : same air duct length (2.2 cm), same very thin mouth hole (1.8 cm x 0.3 cm), and an air entrance quite similar, but a bit narrower on the small flute.
Only the mouth cap is longer on the large model, where the air duct cover is made in 3 parts, two of them following the sides all the flute long.
The large model :
Handler's flutes are made of fruit tree wood, but also in maple or yew. Some are two colored wood mixed.
They wear the Heinrich Handler's monogram : a capital H between two points.
The precision of the work (sharp and neat labium) allied to sharp technical specifications (very narrow mouth hole) and quality woods, lead to high quality nose flutes, with a great rich wood sound, precise in response and very handy and confortable to play.
Here is a sound sample (thanks to the Nosy Diva Miss Birdy K.) :