#158-25 HO Scale Bulk Pack - 25 pair #158 Scale Whisker® Metal Couplers - Medium (9/32") Centerset ShankDetails: The next evolution of model train couplers starts and ends with the Kadee Whisker series of couplers. The scale size and detail of the #58 coupler has long been popular with model railroaders, so we knew we had to offer a Whisker version. Behold the #158 a scale sized coupler with smaller head and knuckle for a more prototypical look. Often referred to as the "Whisker version of the #58", the #158 features an even longer lasting and more