Pentax K-R Operating Manual page 45

Insert the lithium-ion battery or AA batteries into the camera.
iiiiiiiiiiiiiiiiiiiii!i
Use the exclusive battery D-LI109.
When using the battery for the first time, or when the battery has not been
used in a long time, or when [Battery depleted] appears, recharge the
battery.
Note: AC plug cord "Listed, Type SPT-2 or NISPT-2, 18/2 flexible
cord, rated 125 V, 7A, minimum 6ft (1.8m)"
1 Connect the AC plug cord to the battery charger.
2 Plug the AC plug cord into the power outlet.
lamp
plug cord
y charger