The BM-45 will mount into the left end of the "M" bars on my Brompton and not strike the ground when folded. This has been a problem as the left end of the bars ends up very close to the ground when folded. The BM-45 leaves about a finger's width of clearance. It's also attractive and unobtrusive so it doesn't distract from the bike's looks. I, also, like the way it secures in the bar like a quill stem, rock solid.
CatEye BM-45 Barend Mirror Black
BM-45 Barend Mirror Black
Our sleek new ultralight BM-45 barend mirror easily attaches to drop and flat bars, making it perfect for all bikes. Constructed of aluminum and glass for durability and nearly distortion-free viewing, the BM-45 represent the height of handlebar mirror construction and design. Minimal projection from the bar means never having to sacrifice clean aesthetics for critical rear-view safety again.