Precision-machined aluminum with a heavy internal weight (often brass or stainless steel).
Certain long-handle ratchet or socket sets (like those from GearWrench or Capri Tools) occasionally use similar SKU patterns for "Master Sets". Community Perspectives “If you're looking at the Rolex 18238 Go to product viewer dialog for this item. 18838x
New Capri Tools Master Impact Socket Set Review Don't miss out 18838x
Compatible with various plate materials (Aluminum, FR4, POM) to drastically change the "thock" or "clack" of the switches. Performance Review Sound Profile: Users describe the 18838x