Retsch Laboratory Mixer Mill MM 400. Opens in a new window or tab. PreOwned. Top Rated Plus. Sellers with highest buyer ratings; Returns, money back; ... QIAGEN TISSUELYSER I RETSCH MM301 Mixer Mill Grinder for Parts. Cosmetic dings. Opens in a new window or tab. PreOwned. seaslife (25) 100%. or Best Offer + shipping.