Resupply lockers
From TF2 Wiki
Found in every Resupply area of Team Fortress 2, the Supply Closets completely refill health, ammo, metal, and as of the December 11, 2008 Patch, cloak!
Useful Information
The Cabinets are unique in a way that not only do they refill spare ammo, but reload current ammo. Basically, upon opening the closet, your class is restored to respawn effectiveness. Also, since the cabinets function like a medkit, you are instantly doused if you were on fire, even while overhealed.
A Supply Closet is also the only place where you may change your weapon loadout, short of respawn.
General Appearance
The cabinets are a metallic grey, with a health symbol and an ammo symbol marking each door. Inside the cabinets you'll find Ammo and Health kits ranging from small to large.
Strategies Involving Supply Closets
On certain maps such as Dustbowl, the closets are positioned in a way that you may fire at the enemy while staying next to, or relatively near them. Utilizing this positioning one could repeatedly fire into enemy territory while having instantanious reloads and health refills.
Retreating to the Resupply Area rather than waiting to respawn can get you back to respawn effectiveness much quicker without the dying.
