Remove one bottle without cap from the filling machine and put the aphrometer on the bottleneck. The permanent aphrometer remains on the bottleneck during the entire secondary fermentation. A gasket ensures the air-tightness between the aphrometer and the bottleneck.​This aphrometer can be adapted to the following bottlenecks: – Jeroboam. – Special bottles. Stainless steel Manometer: (0/10) Bar.NB: Do not hit, do not drop.