Custom Prism Flippers (for powers not listed under stock items) are available in any power combination. All lenses are chemically hardened glass making them more durable than plastic lenses. The flipper power is clearly labeled with a permanent washable sticker. They can be ordered as either a right handed or left handed flipper (when held by the examiner in front of the patient). Please specify power and direction of prism when held in front of patient. Lens #1 is lens AWAY from handle, lens #2 is CLOSEST to handle. Lens #3 is AWAY from handle when flipped and lens #4 is CLOSEST handle when flipped. Allow 3 weeks for delivery.