The HP HSTNN-CA40 19.5V 2.31A 45W Genuine Original AC Power Adapter Charger is a black AC/DC adapter specifically designed for the HP brand. It is compatible with the HSTNN-CA40 model and provides a voltage of 19.5V with an output current of 2.31 A. This genuine original adapter is designed to power your HP laptop efficiently and reliably. With a unit quantity of 1, this power adapter is a must-have accessory for your HP device.