https://en.wikipedia.org/wiki/SI_base_unit

"The kilogram, symbol kg, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant h to be 6.62607015×10−34 when expressed in the unit J s, which is equal to kg m2 s−1, where the metre and the second are defined in terms of c and ∆νCs.[1]"

The base SI unit for power is the watt. The base SI unit for mass is the kilogram. Yes, this is dumb, but it's the way it is.

[1] https://www.bipm.org/utils/common/pdf/si-brochure/SI-Brochur...