Inclusion Criteria:  Currently wear Biofinity® monthly replacement spherical contact lenses. Distance visual acuity of 20/25 or better with current contact lenses. Good general health (defined by medication use that has not changed within the last month and the absence of medical conditions or treatments that are deemed confounding to the data as determined by the PI). Ability to give informed consent. Willing to spend time for the study, which includes attending two study visits and wearing contact lenses on days between study visits.  Exclusion Criteria:  No current ocular inflammation or infection. Not currently pregnant or lactating.