I think this should be equipped with the Jag, since each wrench should have a different custom sentry.
Stats:
+60% turn speed
+15% firing speed
Smaller hitbox
Can stick to flat surface areas

Sentry has larger placement range, allowing you to be more agile with it.

-10% damage
-20% health
+25% metal upgrade cost (250)
+20 metal build cost (150)