Glass flameworking involves handling and manipulation of materials and tools in the near-field of vision. For many people, use of prescription glasses is beneficial to reduce eye strain and improve clarity of close-up vision. Due to the cost and complexity of manufacturing prescription safety glasses, it is often preferable to use an "over-the-glasses" type of frame that is designed to be worn over a pair of normal prescription glasses: this provides an economical solution that maintains full coverage eye protection.
The VetroSafe X2 Guardian OTG is an over-the-glasses frame designed to be worn over prescription glasses. For best results, following the recommendations below will optimize the performance and comfort of the OTG product.
Check the Rx Glasses Fit
For use with the VetroSafe X2 Guardian OTG, the underlying Rx glasses must be sized appropriately to fit under the safety frame. The maximum frame front width (measured across the entire front of the glasses) should be 135 millimeters or less (5 inches and 5/16ths of an inch). The maximum frame height (measured from the top to the bottom of each lens measured at its maximum height), must be 45 millimeters or less (1 inch and 3/4ths of an inch).
Maximum Rx Glasses Size
| Dimension | Size in mm | Size in inches |
| Total Frame Width | 135 millimeters | 5 5/16ths inches |
| Maximum Lens Height | 45 millimeters | 1 3/4ths inches |
Metal or Rimless Frames Preferred
Plastic frames are lightweight and suitable for everyday wear, but are generally thicker in the front and side temples, which can be less comfortable than a metal frame. Metal frames with a flat "sheet metal" temple style are even better, especially with a lightweight material such as titanium. Rimless frames are another option for those seeking an ultra-light OTG combination.
Improve Clarity with AR Coatings
When combining a base Rx glasses with an OTG eyewear, light can reflect and bounce back and forth in the air-gap between the lenses. When this occurs, a person may see "ghost images" or "halos" especially when viewing a bright source of light or a glint of reflected light from a shiny surface. Anti-reflection coatings (also called AR coatings) reduce the reflectivity of lenses and can eliminate the effect. VetroSafe lenses include anti-reflection coatings as standard - for optimal performance the underlying Rx glasses should also have anti-reflection coatings.
Getting the Best Results
If you have multiple pairs of eyewear, we recommend testing each pair of glasses with the OTG safety frame to determine which one provides the best vision and comfort.
As always, if you have any questions or issues please reach out to us for assistance at support@vetrosafe.com.