These Ray-Ban RB3721CH Replacement Lenses are aftermarket lenses cut in our workshop for the Ray-Ban RB3721CH. Worn or scratched lenses are usually what retires a pair of sunglasses long before the frame gives up, and new ones bring it back into use. You may also see this model written as Ray-Ban 3721.

Ray-Ban RB3721CH Replacement Lenses: fit and measurements

Angular lenses have corners, and that is where a poor cut shows first: a gap at the rim or a lens that will not sit flat. This model is sold in size 59. Each lens is about 67 mm in diameter and 45 mm high. Before ordering, read the code printed inside the left temple: it must say RB3721CH, followed by the size. A lens from another model will not seat properly even if it looks similar.

• Model code: RB3721CH
• Size: 59
• Lens: 67 mm diameter, 45 mm high
• Frame front: metal
• Lens curve: Base 6
• Colours: 20

Lens material, colours and coatings

Tinted lenses are polycarbonate with a Base 6 curve and UV400 protection; clear lenses are CR39 or polycarbonate, depending on the coating. There are 20 colours on this page. Solid tints: blue, green, pink, red, yellow, brown and grey. Gradients: grey gradient and brown gradient. Mirrors: gold mirror, violet mirror, ice blue mirror, black mirror, blue mirror, green mirror and red mirror. Photochromic, which darken in sunlight: photochromic blue, photochromic green and photochromic grey. Clear lenses are also available, with a blue-light filter option. Green stays close to natural colours, grey is the most neutral and brown adds warmth and contrast. Most tints can also be ordered polarized to cut glare: the options for each colour appear under the colour selector. Blue, pink and red come non-polarized only. When you pick a colour, the photo above shows it on this frame.

How to fit them

The front of the RB3721CH is metal. On most metal frames the rim is held closed by a small screw next to the hinge: loosen it, take the old lens out, seat the new one in the groove and tighten again without overdoing it. If you are not confident, an optician can do it for you.

Why change the lenses and keep the frame

Changing the lenses lets you keep a frame that already fits you, and it is also a way to try another tint without replacing the glasses. If you own another pair, there are more models in our Ray-Ban replacement lenses section. The Ray-Ban RB3721 has its own page in the same section.

Frequently asked questions

Are they made by Ray-Ban?

No. They are aftermarket lenses, made independently to fit the RB3721CH. Ray-Ban does not make or endorse them.

How do I know this is my model?

Look inside the left temple, where the model code and size are printed. It must say RB3721CH. If it says something else, search for it in the store or write to us before buying.

Can they be polarized?

Most tints can, and you choose it under the colour selector. Whichever you pick, every sun lens has UV400 protection.

What warranty and returns do they have?

A 3-year warranty on manufacturing defects and 14 days to return them.

Do I get a pair or a single lens?

A pair: one left lens and one right lens, in the tint you select.