These new Hi-Lo polarised sunglasses offer you the dual benefit of having interchangeable light' (amber) and 'dark' (grey) tinted lenses to suit varying light conditions. In practice this means that the amber lenses are perfectly suited to slightly overcast or changeable days (typical English weather!), whilst the grey lenses are ideal for really bright days when the sun is at its peak on those rare occasions when there isn't a cloud to be seen in the sky! Perfect for customers on mainland Europe...