Traditionally, cells and media are first transferred from a cell culture flask to a 15-mL or 50-mL conical tube before centrifugation. These transfer steps require operator labor and time, the cost of the transfer vessel, and introduce the potential for contamination during transfer. With the innovative Cell Culture Flask Adapters, the culture can be centrifuged directly in the flask. Data illustrate that cell yield, cell viability, and endpoint analysis results are comparable when cell cultures are processed traditionally or centrifuged directly in the flask using Cell Culture Flask Adapters. The Cell Culture Flask Adapters are single-piece elastomeric (EPDM) adapters designed to allow centrifugation of T-75† (75-cm2 area) or T-25† (25-cm2 area) cell culture flasks in the Allegra X-15R and Allegra X-12 Series centrifuges using SX4750 and SX4750A rotors. The adapters stand up to the rigors of use (centrifugal force, cleaning, and sterilization) in the bioresearch laboratory.