Audio Connectors - 1/4" TS (Tip/Sleeve - Mono) - Cable End - 1/4" Professional phone plugs are available in TS (Tip/Sleeve - mono) and TRS (Tip/Ring/Sleeve - Stereo) configurations, and are used universally for balanced and unbalanced audio connections between audio equipment, and instruments. Both TS and TRS 1/4" plugs are available in straight, or right angle configurations. TRS also available in Mil Spec, and thin profile Bantam Audio sizes for various audio application such as bantam audio patch bays.