From the product description, check product page for current description, price and availability:

Yeast Starters made easy!

This can of concentrated wort is perfect for giving your yeast the “Propper” start, whether preparing a cold-pitched lager, a high gravity brew, a yeast pack nearing expiration or just whenever a yeast started is required. The Propper Starter allows you to quickly and easily prepare the yeast for your next batch of beer, cider or mead without dealing with messy dried malt extracts, or waiting for boiling & cooling. Propper Starter increases both the biomass and vitality in your yeast, ensuring your brew ferments correctly. Each 16 oz. can of condensed wort creates one 1 L starter.

How to Use Propper Starter Condensed Wort Can:
– Sanitize 2 L Flask, stir bar, yeast pack and the top of your Propper Starter can
– Swirl your can of Propper Starter and add to flask
– Add 16 oz. of bottled, distilled, or boiled & chilled water to flask
– Pitch yeast, cover flask with foil and mix for at least 24 hours

For more info, visit the product pages for FAQS