Improve the appearance and operation of your HO Scale models with the all-new Accumate(R) PROTO HO scale-size knuckle couplers. These magnetic couplers represent the first correctly scaled and proportioned replicas of the AAR type E coupler. Through the years, limitations of the manufacturing process resulted in knuckle couplers that are actually too wide, too long and too short when compared to the real thing. As a result, cars are spaced too far apart when coupled together and the standard mounting box (engineered to accept over-sized couplers) is wider than an actual center sill, making it impossible to detail this important area. Accumate PROTO HO couplers are correctly shaped and sized to overcome these limitations. When mounted in their own draft gear box, the length of the coupler provides scale striker to coupler pulling face distance, making any cut of cars, or an entire train, much more realistic. The draft gear box has been detailed to represent the sills, draft lugs and coupler yoke found on an actual car. The box is long enough to reach all the way to the bolster on a typical car, but can be cut shorter for special applications, such as HOn3 equipment. ? Although the profile of the Accumate(R) PROTO HO couplers is smaller, it is compatible with all types of standard knuckle couplers currently used in HO Scale. While the width of the shank has been decreased to fit the narrow draft gear, the depth of each half-shank has been increased. This gives the couplers 95% of the cross section and strength of a standard Accumate coupler.  Refitting your equipment is fast and easy, as the new draft gear box is designed to fit the standard box found on the floor of most kits. It is narrow enough to fit entirely between the sides of the standard box and can be installed on the existing surface while maintaining the correct coupler height. The new mounting screw holes have also been placed so as not to interfere with any existing coupler mounting holes.