This flow control device is designed to be used with our oxygen cylinder and regulator that can be purchased separately.Pure oxygen is the best way to get your yeast off to a cracking start. Simply use this high pressure and high-capacity disposable tank to boost dissolved oxygen levels in your cooled wort.Oxygen is great to use with high gravity beers or pilsners where you are trying to build up a large population of yeast.We would recommend the use of a diffusion stone.  These small diffusion stones create very fine bubbles of oxygen in your wort and help the oxygen to dissolve into solution faster.If you want a really nice option we would recommend the use of an oxygenation wand, available in 2 Micron or 0.5 Micron kits as this is a bit more ergonomic as you have a rigid stainless tube to force the stone to the bottom of the fermenter rater than it floating to the surface.This flow control device is designed to be used with our oxygen cylinder and regulator that can be purchased separately.Instructions Attach the regulator to the top of your disposable cylinder.  Turn pressure up to 1-10psi.  Immerse diffusion stone in wort for 1-2 minutes. Then dial the flow meter up to 1.0L/min. The time it takes to saturate will depend on volume, temperature, depth of vessel, and type of stone (0.5mm recommended)NOTE: Wort must be cold.  It is extremely difficult to get oxygen to dissolve into hot wort so it’s essential to cool wort completely before starting this process.For a 20L batch in a standard 30L HDPE fermenter at room temperature, please see the table below.MethodDO ppmTimeSiphon Spray4 ppm0 sec.Splashing & Shaking8 ppm (maximum)40 sec.Aquarium Pump w/ stone8 ppm5 minPure Oxygen w/ stone0-26ppm60 sec (12ppm)According to Chris White (The founder of White Labs Yeast), (2010, p. 79), the ideal injection rate for pure oxygen in a 1.077 wort is 1 litre per minute. This is the most efficient way to achieve the required 10-14ppm. For a weaker wort, say 1.048, and using the same flow rate of 1 litre per minute, you would only need about 45 seconds to achieve the same oxygen levels. If you decide to inject the oxygen at 0.5 litres per minute, you will need to double the injection time (i.e. 2 minutes for a 1.077 wort and roughly 90 seconds for a 1.048 wort). You get the idea…HOW TO 1. We recommend boiling your 0.5micron stone for a few minutes to sanitise the stone / wand. Work out with the table above how long you need to inject the oxygen and have a timer (or google home / alexa) on standby. (please see warning at the bottom for boiling)2. Open up the regulator to release oxygen, adjust your flow meter to 1L a minute then submerge into your fermenter and start the timer. NEVER put your stone into wort without air flow. It could clog!3. If you’re pushing too much air through at a high rate, the bubbles will break at the surface and not saturate / dissolve into the wort. This is why 1L is easy to measure and ensure enough saturation as possible.4. If you’re finding 1L min is breaking at the surface, slowly adjust lower. If you break flow the stone could clog.5. Take out your wand/stone and dump into some steriliser liquid with the flow still on.6. Then take out and turn off the regulator.7. We recommend giving it a quick boil after use to keep it clean and sanitary. (Remember never to touch the stone with your fingers (use gloves) as the oils in your skin can clog it.)WARNING Do not boil over an open flame! Pure Oxygen is EXTREMELY FLAMMABLE. Use the kettle! or an electric urn. Or freshly boiled still hot liquid from the stove if you must.Specifications Type: Pure Oxygen Air Flow Meter Thread type: MFL Connector Pieces: FFL x 8mm duotight push ins Body material: PMMA Pressure: 0.1Mpa Accuracy: 0.5% Temperature: 0-60C Float material: Agate ball O-ring material: Silicone Height: 93mm Width: 22mm Measure range: 0.1-1.5L