Grinder 1b 2 5Human Grade Grinder 1B (2. 5") Aluminium Herb Grinder The Human Grade Grinder 1B steps up from the compact 1A with a 2. 5 inch diameter, giving you noticeably more grinding capacity without sacrificing portability. After testing both sizes back to back, the extra half inch makes a real difference for heavier sessions or when grinding for multiple vaporizer loads at once. The diamond cut teeth perform consistently across the larger chamber, and the