Microcentrifuge tube racks are reversible 96-well racks that hold tubes in an 8 × 12 format.  One side of the reversible rack holds 96 1.5 mL, 1.8 mL or 2.0 mL microcentrifuge tubes while the other side holds 96 0.5 mL tubes.  Autoclavable racks are alpha-numerically…