Shiny new freehub body, Shimano or Campy compatible. Shimanos are silvery; Campys are black.
Shimanos are available in steel for un-spidered, as in custom cassettes and some high-end cassettes.
Also available in alloy for spidered cassettes. (Don't use an alloy body with a loose cassette: you'll ruin it!)
Oil the pawls on installation and periodically afterwards; mineral oil or Phil Wood oil is suggested. Do not use grease on the pawls!