Mini CO2 Regulator.  0 to 60 PSI.  Screw on to MFL threaded disconnect.  3/8″ thread for 16 gram CO2 cartridge.

Use to serve your ball lock keg of homebrew on the go or as a backup in case you run out of CO2.  Unlike handheld portable CO2 chargers, this mini regulator has an adjustable pressure knob.

Update: Since this post was published the price, availability or promotion has changed.  Check the product page for current description, price and availability.  Also: Today’s Deals on Amazon

0~60 Psi Home Brew Premium Regulated Co2 Charger Kit Anodised Aluminium Body

Also Consider: Leland Mini CO2 Regulator – Review | Portable Draft Serving Options | 5 Recent Keg Finds