Master Lock - Universal Size Fits 1-7/8", 2", and 2-5/16" Couplers - Trailer Locks #389DAT Master Lock - Universal Size Fits 1-7/8", 2", and 2-5/16" Couplers - Trailer Locks #389DAT Features Universal coupler lock fits virtually all 1-7/8", 2", and 2-5/16" trailer couplers. This lock protects unattended trailers and guards against tow-away theft. The bright red finish discourages thiefs from messing with your trailer. Resists rust and corrosion. Simple installation and removal. Advanced locking mechanism resists picking and prying. USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.