A buddy line is a line or strap physically tethering two scuba divers together underwater to avoid separation in low visibility conditions. A buddy line is usually a short length of about two meters with a floating element between divers to reduce risk of snagging on the bottom. A buddy line is a means of communication. It doesn't need to be particularly strong or secure, but should not pull off under moderate loads. Divers may communicate by rope signals, but more usually just use the line to attract attention before moving closer and communicating by hand signals. The disadvantage of a buddy line is an increased risk of snagging and entanglement. Divers may need to disconnect the line quickly at either end in an emergency, which is done via a quick release mechanism or by cutting the line, both of which require at least one free hand. A velcro strap requires no tools for release and can be released under tension.