MHW-3BOMBER Astra Series Bottomless Portafilter 58mm Black Product Information Fine Filtration Holes: Designed with precision filtration holes, this Bottomless Portafilter ensures even extraction while minimizing the outflow of fine coffee grounds, resulting in a cleaner and more flavorful cup of espresso. Fully Metal Build: Crafted from high-quality SUS304 stainless steel and aluminum alloy, this Bottomless Portafilter boasts a robust, fully metal construction that is both durable and resistant to corrosion, ensuring longevity and ease of maintenance. Comfortable Grip: The ergonomically designed handle offers a smooth and rounded grip, providing comfort during extended use and enhancing user control during the espresso extraction process.