Shopping Cart
Rotate your device
Please Turn Your Device

Whats the difference between our lenses?

We often get the question: What’s the difference between the lenses? So here's a few paragraphs letting you know what the differences are - allowing you to make an informed decision about which lenses will be most beneficial for you and your dog.

First of all, ultra violet light is known to cause various types of damage to the eye.  Eye health is the reason we started making Rex Specs - one of our dogs was getting chronic sunburn to the eye lid, and one was diagnosed with pannnus. So, we wanted to make sure our lenses would protect from UV rays.  Polycarbonate is the perfect material. Polycarbonate lenses are used for sunglasses, ski goggles, riot shields, and many, many other applications. It’s a great material because it blocks 99.9% of UVA and UVB rays, and is shatter resistant. To read more about it we suggest looking at

Another way to describe our lenses is by their Visible Light Transmission (VTL). This is a measurement of how much light the lens allows to pass through to the eye. A low VTL allows very little light through, and a high VTL allows a lot of light to pass. The amount of VLT has been broken into 5 categories - they are as follows.

Category 0 - 80-100% VTL

Category 1 - 46-79% VTL

Category 2 - 18-45% VTL

Category 3 - 8-17% VTL

Category 4 - 3-8% VTL

Since all of the lenses are made of the same material (polycarbonate) they all offer the same UV protection (99.9%). They are also durable and shatter resistant - in fact, our Rex Specs Original goggle and lens has passed the ANSI Z87.1 - 2010 impact resistance test. You can see the video footage HERE.

We have found that the clear lenses are the longest lasting and we use them on our personal dogs 90% of the time. Although all of the lenses scratch with the same force - because they are all made of the same material - the scratches on the clear lenses are least noticeable to the dog. Our smoke lens are second best at 'hiding' scratches as the tint is impregnated into the lens.  The mirrored lenses we offer are in fact the same lens as the smoke lens, but with a sprayed coating on them to give them a mirrored look. When the coating on the mirrored lenses scratches, it’s more noticeable than with the non-mirrored options. 

Finally, dogs do not see the same way that humans do.  Their visual acuity is estimated to be around 20/75 compared to humans who can see 20/20.  Therefore, they may not notice the scratches in the lenses as easily as we would. This is why we tell our customers to use the lenses until they're totally beat up. Check out the photo below of our dog Tuckerman with his 'used' lenses. 


Dogs do have some advantages. For example, they see in dim light better than us, and can see moving objects at a distance better too. They also have better peripheral vision due to the placement of their eyes. They also have amazing sniffers. Their nose is incredible and anything they lack with their eyesight is more than made up for with their sense of smell.  

Below is a list of our lenses and the VLT category of each lens we offer

Size Original

Clear - category 0

Smoke - category 2

Red Revo - category 2

Blue mirror - category 2

Silver mirror - category 2

Blue Revo - category 3


Size Small

Clear - category 0

Smoke - category 2

Red Revo - category 2

Blue Revo - category 2

1 comment

  • Ralph on

    Hi. Your advice please. I have two boxers. The white one has just had the second occurrence of corneal ulcer. She has very little pigment on the eyelids and her eyes are vulnerable to sunburn. And of course they both love sunbathing in the Queensland, Australian sun which has very high UV content. I expect its the original size I should get? Please advise on which style of lens you would buy if this was your dog. Hope to hear from you soon


Copyright © 2015 · All Rights Reserved · Rex Specs

  • american express
  • diners club
  • discover
  • jcb
  • master
  • paypal
  • visa


Sign up to receive great adventure stories of our customers, specials, and more exclusive content!