Campy...here's a link to the HK45 owners manual.
Heckler & Koch - USA
The variants to the HK45 are the same as the USP...which is also pasted below.
USP Variants:
Variant 1:
Double action/single action with "SAFE” position. Control lever (manual safety/decoking lever) on left side of frame.
Variant 2:
Double action/single action with "SAFE” position. Control lever (manual safety/decocking lever) on right side of frame.
Variant 3:
Double action/single action without "SAFE” position. Control lever (decocking lever) on left side of frame.
Variant 4:
Double action/single action without ”SAFE” position. Control lever (decocking lever) on right side of frame.
Variant 5:
Double action only with ”SAFE” position. Control lever (manual safety) on left side of frame.
Variant 6:
Double action only with ”SAFE” position. Control lever (manual safety) on right side of frame.
Variant 7:
Double action without control lever (no manual safety/decocking lever)
Variant 8:
Double action without control lever (no manual safety/decocking lever)
SPECIAL VARIANT FOR GOVERNMENT AGENCY
Variant 9:
Double action/single action with control lever (manual safety/no decocking function) on left side of frame.
Variant 10:
Double action/single action with control lever (manual safety/no decocking function) on right side of frame.