The study will explore in vivo lens dehydration rates across a 12hr wear period for the study lenses.

The study will explore in vivo lens dehydration rates across a 12hr wear period for the study lenses. The primary outcome variable for this study is the loss in lens weight over the day, which will indicate the amount of dehydration that has occured.

Inclusion Criteria:

1. Is at least 17 years of age and has full legal capacity to volunteer;
2. Has read and signed an information consent letter;
3. Is willing and able to follow instructions and maintain the appointment schedule;
4. Is a current wearer of soft contact lenses and has worn them (any brand) more than 3 months.
5. Is able to wear lenses for at least 12 hours a day.

Exclusion Criteria:

1. Is participating in any concurrent clinical study;

2. Has any known active* ocular disease and/or infection;

3. Has a systemic condition that in the opinion of the investigator may affect a study outcome variable;

4. Is using any systemic or topical medications that in the opinion of the investigator may affect a study outcome variable;

5. Has known sensitivity to the diagnostic pharmaceuticals to be used in the study;

6. Has undergone refractive error surgery;

   • *For the purposes of this study, active ocular disease is defined as infection or inflammation which requires therapeutic treatment. Mild (i.e. not considered clinically relevant) lid abnormalities (blepharitis, meibomian gland dysfunction, papillae), corneal and conjunctival staining and dry eye are not considered active ocular disease. Neovascularization and corneal scars are the result of previous hypoxia, infection or inflammation and are therefore not active.

From dispense up to 12 hour for each study lenses