Mittens (Or possibly gloves) built with two layers: A cooling layer near the skin, circulating either air or water from an external source; and an insulating layer, probably involving a layer of impermeable foil or very tightly knit kevlar.
The pad of the mitt contains heating elements and thermistors
(or the elements can be monitored themselves), so that when the mitts are placed over a cool section of plastic, more power is driven through the heating element, and then cut back when the plastic reaches the right temperature.
Power on, max temp, and max delta T are set by foot controls.
Temp is displayed on back of mitts, in varying colors, along with a label to discourage nose scratching and the grasping of pressurized containers.