ROCKBROS SP350 cycling glasses have a flexible TR90 frame and come in polarized and photochromic versions. These are separate lens options, not two properties of the same lens: the polarized version helps reduce glare, while the photochromic version changes tint in response to UV radiation.
pandealia.euThe best coupons from Chinese stores, prices and price history in one place.ROCKBROS SP350 cycling glasses have a flexible TR90 frame and come in polarized and photochromic versions. These are separate lens options, not two properties of the same lens: the polarized version helps reduce glare, while the photochromic version changes tint in response to UV radiation.
Which version should you choose?
Polarized lenses are made from TAC and have a stated light transmittance of approximately 10.33%. They are therefore quite dark and best suited to cycling in sunny conditions. Polarization helps reduce distracting glare, for example from wet roads. The tint of this version does not adjust automatically.
Photochromic lenses are made from polycarbonate (PC) and respond to changes in UV intensity. Their stated light transmittance changes from 49.15% before darkening to 8.98% when darkened. This means riders do not need to change glasses when moving between different lighting conditions, although the change in tint depends on UV exposure. The colored photochromic lenses change to a violet-pink tint.
A category 3 filter is specified for the glasses. The light transmittance of the polarized version and the fully darkened photochromic version is consistent with a dark filter suitable for sunny conditions. Before darkening, however, the photochromic lens lets through considerably more light, so category 3 cannot be applied to its entire transmittance range. Dark lenses are not suitable for riding in low light or at night.
Frame, dimensions and weight
The TR90 frame is flexible and lightweight. When choosing glasses, compare their dimensions with a pair that already fits you: neither the material nor the frame width alone guarantees a comfortable fit on every face.
The stated dimensions of the SP350 are:
- Overall frame width: approximately 142.54 mm
- Lens height: approximately 60.70 mm
- Temple length: approximately 133.60 mm
- Inner width between the temples: approximately 134.81 mm
- Distance between the nose supports: 5.28 mm
- Upper distance between the lenses: 90.10 mm
The measurement points for the last two figures are not described in detail. The 5.28 mm figure should therefore not automatically be treated as a conventional nose bridge width.
The polarized version weighs approximately 27 ± 3 g, while the photochromic version weighs 28 ± 3 g. The difference between the stated weights is small; on longer rides, how the frame fits on the nose and behind the ears will be especially important.
UV protection and anti-fog coating
The SP350 has UV400 protection against UVA and UVB radiation in the 280–400 nm range. It also has an anti-fog coating that helps reduce fogging. However, the lenses may still fog during intense exertion or changes in the weather.
Impact resistance is described as “level 1”. Without a named test or standard, this designation does not establish a specific level of protection.
