Catalyzes the hydrolysis of ATP coupled with the exchange of H(+) and K(+) ions across the plasma membrane. Responsible for potassium absorption in various tissues. ATP + H(+)(in) + H2O + K(+)(out) = ADP + 2 H(+)(out) + K(+)(in) + phosphate Composed of two subunits: alpha (catalytic) and beta. Found in skin, kidney and distal colon. Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIC subfamily.