Its a resistance heat source, Ive seen a similar one used for soldering serial number plates onto heat exchangers and radiators at a place I worked for years ago, the number plates were ready tinned, just a brush of bakers fluid on the back and squeeze up with the pliers,
On their web site it says "Environmentally Sustainable Bioplastics and Radio Frequency (RF) Welding, Heating & Sealing Technologies" and those tong things look like they are for plastic welding to me.