This will be an up to six months, subject-masked, contralateral, parallel-group, randomised, daily wear study. All subjects will wear the Test lens in one eye and the Control lens in the other eye. Data from the first four weeks of Test and Control lens exposure will be used for the FDA 510 (k) submission.

Inclusion Criteria:

• Willing and able to sign the informed consent form
• Aged ≥18 years old
• Experienced wearer of rigid gas permeable contact lenses
• Subject's habitual contact lenses must be made of Contamac's Optimum Extra (roflufocon D) material
• Subjects must have owned spectacles or contact lenses prior to enrolment for this trial
• Spherical power between -10.00 D and +10.00 D (at vertex distance 0 mm)
• Corneal astigmatism ≤2.00 D

Exclusion Criteria:• Eye injury or surgery within 3 months immediately prior to enrolment for this trial

• Pre-existing ocular irritation that would preclude contact lens fitting
• Currently enrolled in an ophthalmic clinical trial
• Evidence of systemic or ocular abnormality, infection or disease which is likely to affect successful wear of contact lenses or use of the accessory solutions, as determined by the investigator
• Any use of medications for which contact lens wear could be contradicted, as determined by the investigator
• Current extended-wear users (sleep-in overnight)
• Current monovision lens wearers
• Current wearers of multifocal contact lenses
• Current wearers of toric contact lenses (front surface design)
• Current wearers of astigmatic contact lenses (posterior surface design)
• Has a reported "Strong" comfort or vision preference between each eye with their habitual RGP lenses
• Unacceptable fit of habitual lenses
• Pregnant women and nursing mothers
• Best-corrected visual acuity worse than 6/9 (LogMAR: +0.20; Snellen decimal: 0.63)