3 Assembled #148 Whisker® Metal Coupler - Medium Centerset Shank The #148 Whisker® Metal Coupler will work anywhere a NO.5® Coupler will work. This industry leading coupler features an all metal coupler head, shank, and Whisker® centering spring and comes complete with and insulated draft gearbox and lid. The #148 Magne-Matic® Whisker® Metal Coupler may be mounted with the included #242 Snap-Together Gearbox or with other manufacturers cast-on coupler pockets. It is not recommended to use a metal coupler directly on a metal surface or in a metal draft gearbox to avoid possible electrical crossover and shorting that may cause damage. Use the provided insulated gearbox or insulated #28 coupler. Refer to our helpful Coupler Conversion Charts to determine the appropriate coupler to use on your model. Two pair per package Package Includes: (2) Pair Assembled #148 Whisker® Metal Couplers in #242 Gearboxes (2) Extra #622 Knuckle Springs #148 Whisker® Metal Coupler Features: Material - Metal Shank Length - Medium (9/32") (center hole to back of coupler head) Coupler Offset - Centerset Knuckle Spring - #622 Centering System - Whisker® Head - Standard Head #242 Snap-Together Gearbox Features: Material - Insulated Plastic Lid Type - Snap-Together Dimensions - 7/16"L x 5/16"W x 1/8"H Mounting Specifications: Mounting Height - 29/64" Centerline - 25/64" Trip Pin Height - 1/32" Center Hole - 2-56 Insulated Screws are the most commonly used