Gazer
Gazer is an older form of the place-name Gezer; UPDV reads "Gezer" in both surviving occurrences. The site marks the western terminus of David's pursuit of the Philistines after the Yahweh-given victory in the Rephaim valley.
The Western End of David's Philistine Rout
The narrative in Samuel closes the second Philistine engagement with a long-range pursuit: "And David did so, as Yahweh commanded him, and struck the Philistines from Geba until you come to Gezer" (2 Sa 5:25). The Chronicler's parallel preserves the same terminus, with the starting point given as Gibeon: "And David did as God commanded him: and they struck the host of the Philistines from Gibeon even to Gezer" (1 Chr 14:16). Gezer marks where the rout finally stops.