Does grey refer to the lenses or frame?

It may describe either part depending on the design. Check the colours separately instead of assuming the entire pair has one tone.

Do transparent and opaque grey frames look the same?

No. A transparent front lets light through the frame material and creates a different visual presence. This does not describe the sun filter's properties.

Does grey only work with cool colours?

No. Wear it with beige, brown or brighter colours for contrast. Consider the whole outfit and how prominent you want the glasses to be.

Are grey lenses necessarily photochromic?

No. Photochromic technology must be specified. Grey can also be a fixed tint with different features depending on the design.

Do darker lenses provide more UV protection?

Tint and ultraviolet protection are different properties. Check the stated protection and filter category; colour alone confirms neither.

Which measurements should I compare with my current glasses?

Compare front width, bridge and temple length. Do not confuse the width of one lens with the width of the entire frame; use glasses that stay stable as a reference.

How do I clean lenses without damaging the finish?

Follow the design's instructions, remove dust first and use a clean microfibre cloth. Avoid rubbing with clothing or paper and do not use cleaners without confirmed compatibility.