Jonas Siegenthaler is a big defenseman hailing from Zurich, Switzerland. As of the final rankings, he was rated the 12th best European skater entering this year's draft. That is a good position to be in, and it most likely means that Jonas will be taken around the second round of the draft.
Jonas has the size to compete at the NHL level, standing at 6'2" and weighing 214 lbs. Considering his age, there is a chance he could gain even a little more weight on top of that, which would really give him a powerful frame.