Astoria Group Head Dispersion Disk (Showerhead) Standard-size dispersion disk that spreads water evenly across the group screen during extraction. Held in place by the group screen screw. This is Astoria's "Water Spout Unit Support," the most common size used across Astoria group heads. SPECIFICATIONS Outside diameter: 59 mm Height: 9.5 mm Center hole diameter: 5.5 mm Astoria part #: 4825627 COMPATIBILITY Fits: Astoria group heads using the standard-size dispersion disk Works with: group screen and screen retaining screw INSTALLATION Simple DIY replacement during routine group head cleaning or screen service. PRO TIPS Uneven extraction or channeling is often a clogged or warped dispersion disk, not the puck, soak it in espresso machine cleaner and backflush regularly, and replace it once the holes are visibly worn or the disk no longer sits flat.