Six-piece Gyratory Screen with 16 screens per section, type GM 631-166 of fire and vermin-proof all-metal construction for flour mills and food-processing concerns. This gyratory screen obtains its novel appearance through its shape and matt metal-finish. Its most progressoie feature is that aluminum frames of main screens with inserted frames on both sides can be pulled out of their individual sections like drawers. Rapid control is afforded and frames are easily changed over.