Heavy-duty, readjusting tweezers are available in sharp or rounded ends with fine serrated grips. Tweezers are made from rigid, impact-resistant and temperature-resistant polymethylpentene (PMP). Able to withstand temperatures up to 392°F (200°C) for short periods and 356°F (180°C) continuously. PMP is ideal for use with diluted and concentrated acids, alcohols, aldehydes, bases, esters, mineral oils, and vegetable oils. Autoclavable.