Unit might be used because in open box.

The HP iPAQ Standard Battery for 4100 Series H4150 H4155 is a high-quality battery designed specifically for Hewlett-Packard devices. With a capacity of 1000mAh, this battery is compatible with the HP iPAQ 4100 Series models H4150 and H4155, ensuring reliable and long-lasting power for your PDA or mobile device. The HP brand guarantees optimal performance and compatibility, making this battery a dependable choice for extended use on the go.