CRS2010-FW-4R99ELF is a high-power anti-surge chip resistor from the CRS Series designed for pulse power applications, high-voltage applications, consumer electronics, telecommunications, and power supplies. The device features a 1 W power rating at 70°C, a maximum working voltage of 200 V, and a maximum overload voltage of 400 V, with an operating temperature range of -55°C to +155°C. It has a resistance value of 4.99 ohms with ±1% tolerance and a temperature coefficient of ±100 PPM/°C. The resistor is constructed with a ceramic substrate, resistive element, and lead-free conductor with tin plating, offering excellent surge performance and reliability. Its compact 2010 package size (5.00 mm × 2.50 mm) and RoHS compliance make it ideal for modern electronic designs requiring robust surge protection and thermal stability.