A widget goes in the bottom of a can, and IIRC, releases nitrogen when you open the can forming lots of microbubbles in the beer, creating a smooth head on pouring.
A sparkler is like the aerator on a hand washing tap, it screws on to the beer dispensing tap (the one fixed to the bar, not a keg tap). It aerates, or they used to. Beer technology has moved on a lot in the more-than-a-decade since I was the wrong side of the bar.
A sparkler is like the aerator on a hand washing tap, it screws on to the beer dispensing tap (the one fixed to the bar, not a keg tap). It aerates, or they used to. Beer technology has moved on a lot in the more-than-a-decade since I was the wrong side of the bar.