PHT Thin Film Wraparound Chip Resistors Vishay / Sfernice PHT Thin Film Wraparound Chip Resistors feature thin film technology and a wide operating temperature range of -55°C to +215°C in four case sizes: 0603, 0805, 1206, and 2010. The PHT series offers a temperature coefficient down to 15ppm, tolerance down to 0.05%, and gold terminations. Vishay / Sfernice PHT Thin Film Wraparound Chip Resistors are ideal for downhole applications and anywhere parts need to be able to withstand severe conditions, including temperatures as high as +215°C powered and up to +230°C unpowered).