Plastic kegs are a potential game-changer for the sale of draft beer in bars and other foodservice venues, with several major brewers aggressively pushing them.

Carlsberg, Denmark’s leading brewer, plans to transition all of its trade draft business to plastic kegs from steel by 2020, according to a Bloomberg Business report. Other brewers using plastic kegs include Anheuser-Busch InBev and Heineken.

Plastic kegs give beer a shelf life of up to 30 days, compared with about a week for steel. This allows foodservice venues to increase the variety of draft beers on tap—seen as a crucial advantage as brand loyalty in beer declines, along with overall sales volume.

Carlsberg produces its plastic kegs in-house, with a technology it calls DraughtMaster. One advantage from Carlsberg’s standpoint is that pubs and others who use DraughtMaster are incentivized to stick with Carlsberg as their sole supplier.