Here are instructions for finding the right RGE Shade Control Clip-On for your eyeglasses. The RGE Shade Control Clip-Ons have a spring loaded bridge that automatically fit to the width of your eyeglasses. The trick is to determine what shape and size lens will work.
STEP 1 MEASURE YOUR FRAME. You will need a millimeter ruler.
Measure the horizontal measurement of one lens and write it down. See below:
Measure the Vertical measurement of one lens and write it down. See below:
STEP 2. FIND A SIMILAR CLIP-ON SHAPE
Go to the Clip-On Shades page on our site. Look at the selection of clips and determine which shape is closest to your glasses. There might be several close options. There are 3 shapes that look close to the eyeglass frames above, the 'Oval', the 'Rectangle', and the 'Round'. (The names are not particularly important. Oddly, the 'Rectangle' shape actually fits the frame above best.)
Click on Clip-On with the closest shape to go to that product page. Once on the product page find the Fitting Chart in the images. Click on the image and look at the Horizontal and Vertical measurements. If you find one that matches closely then right click it and save the chart to your computer.
Next, print out the image on standard 8 1/2 x 11 inch paper. (The shape/size images will print out actual size.)
Place the left lens side of your glasses face down on the image closest to the size you need. Do the shape and size match?
If the measurements are good but there appears to be a gap where the clip-on isn't covering the whole lens, then try a different clip-on shape.
If the clip-on is a millimeter larger vertically than your eyeglasses, that should not be an issue.
If your horizontal measurement is close but not exact, then opt for the larger clip-on option. For example, a horizontal eyeglass measurement is 48 and you find a clip with a perfect shape but comes in a 47 and 49 size then opt for the 49 size clip.
Finally, after you receive your new clip-ons, try them on your eyeglasses. They should fit well. If they are a bit off then the prongs can be adjusted to loosen or tighten the fit. The best way to do that is to go to a local optician and ask them to do it. You can try it yourself with a pair of needle nose pliers, just be very gentle.