Color: black. Material: aluminum. Spacer for Tubes in Beckman Coulter Rotors for use in Ultracentrifuge Rotor TLA-120.2 (part #s 357656, 335650) Required Spacer for Tubes: 2.0 mL Quick-Seal Polypropylene Tube, 11 x 32 mm (part # 344625) 1.5 mL Quick-