The wire can modify to any shape for cutting.
Since it is powered by 2 AAA battery (quite powerful, u can use 1 battery),
it will melt the foam before it touch it, so the hot-wire will not change it's shape during "cutting".
the nylon tie in the front stop the battery holder and the screw at the tail make a ring for hanging in tool-shelf.
Using hot-air gun to soften and bend the PVC as u like.
** Please remind that u need to bend PVC and cut foam in well-ventilated area.
U can see how it works in this video (0:43).
Also, U can use this knife to make a large stamp !!