Details Y&Y Belay Glasses "Kilnsey Neck" is a very real and potentially serious issue for many climbers, caused by standing looking up for far too long. Avoid it with a pair or prism glasses, like these from Y&Y. BK7 prisms made from high quality optical glass give you a perfect view of your climber without having to crane your neck. The prisms are compact, so good peripheral vision is maintained for safe movement on uneven crag bases. They feel solid and well made. I'm an engineer so appreciate good construction. They are ideal for belaying both leaders and top ropers and are most useful for my coaching with prolonged looking up! - Steve McClure Anyone who belays from below on the regular should consider a pair. We think they should be standard issue for climbing centre staff and SPA instructors too. Weight: 36g High transparency prisms Stainless steel frame Memory alloy arms Silicon nose pads - mouldable into shape Firm glasses case included Specifications Belay Glasses