The Reference Series2 of wooden cartridges are hand-crafted at Grado Labs from a Australian Jarrah wood. An intricate procedure of curing is done between production steps to achieve optimal sonic quality. This series generator/stylus module is not replaceable allowing a redesigned one-piece magnetic circuit and a reduction of chassis resonances. The Reference Series2 utilizes manufacturing and assembly techniques that result is musical perfection. The Reference Series2 should be used with only the finest equipment. Recommended tracking force 1.5 to 1.9 grams.