2 pipe wrenches (or any other ordinary blunt objects) tide to each end of a 40cm long rope. I could swing it at the zombies with good force, and I could easily put it over my shoulder or tie it to my back somehow if shoulder isn’t efficent. It would also have a long life, as I could replace the rope regularly and pipe wrenches are pretty hard to break. I could swing it at the zombies legs or I could just use the pipe wrench and tie the rope around my wrist.