Tip Size: 4.5mm outer diameter, 3.0mm inner diameter (with a central pin).
Voltage: (19.5text{V}) constant.
Wattage: (45text{W}), (65text{W}), or (90text{W}). Tip: Using a higher-wattage adapter (e.g., (90text{W}) instead of (45text{W})) is completely safe, as the laptop will only draw what it needs.
Common Compatibility: HP Pavilion, Envy, Spectre, EliteBook, ProBook, and Stream series