We have sold this knife for over 20 years. It has a sealed thermostat in the tip of the steel blade and measures 10" long and 2" wide. The temperature is preset at just the right temperature for uncapping. Using a heated knife is easier and allows you to move down the frame faster. Knife is guaranteed by the manufacturer for 1 year with all warranties handled by the manufacturer.
I have used different knifes, a speed master and now the speed king. Both worked perfectly all day. My desert partner brought over his new import, from Italy not china! and we did a shootout. After 15 minutes he was waiting for my speedking, it was hotter, faster, lighter and the end angle lets you regulate how deep you go. The import knife was a big disappointment. My knife is from 2010 and is still working perfectly.