58mm blind filter for standard 58mm group handles, designed to the normal filter sieve in the portafilter. Enables backflushing on automatic espresso machines that have a pressure release mechanism. Compatible with cleaning tablets for maintenance cycles, allowing convenient backflush without disassembly. Ideal for commercial espresso machines and any setup using a 58mm portafilter and group head. Key benefits: helps remove coffee oils and residues, maintains machine performance and pressure stability, supports routine cleaning, and can extend the life of the group head. Use scenarios: 1) In a busy cafe with an automatic espresso machine, perform daily backflush by inserting this blind filter into the group handle and using cleaning tablets to clear internal passages. 2) During routine service in a restaurant or caf, backflush to remove buildup and keep extraction consistent. 3) In a home or office environment with a 58mm portafilter, conduct periodic backflushing to maintain cleanliness and performance.