#803 Plastic Couplers & Plastic Gearboxes - Black - On3 Scale This industry leading coupler features #803 Plastic Couplers, and #846 On3 Scale centering spring and comes complete with Plastic Gearboxes and lids. 0-48 Mounting Screws are included. #803 Coupler Instructions Two pair per package UPC: 765484008033 Made in the U.S.A. On3-Scale Simple Drop in Design Trouble Free Operation World-Renowned Quality & Performance They just Last & Last & Last... Package Includes: (4) Each #803 Plastic Couplers - Black (4) Each #803 Plastic Gearboxes & lids - Black (6) Each #846 On3 Scale Centering Springs (2) Extra #847 On3 Scale Knuckle Springs (8) Each 0-48 x 3/8 Screws #803 Plastic Coupler Features: Material - Plastic Shank Length - (17/64") (Back of head to center hole of Draft Gearbox) Coupler Offset - Centerset Centering Spring - #846 On3 Scale Centering Springs Knuckle Spring - #847 On3 Scale Knuckle Springs Works In Place of - #807 Couplers Works With - On3 Scale Draft Gearboxes #803 Plastic Draft Gearboxes & Lids Features: Material - Plastic Dimensions - 37/64"L x 3/8"W x 11/64"H Works With - #808 Couplers Mounting Specifications: Mounting Height - 5/8" Centerline - 9/16" Trip Pin Height - 1/16" Mounting Holes - 0-48 or 0-80 screws are the most commonly used screws. (Screw length will vary) Recommended Tools: #813 On3 Scale Coupler Height Gauge #231 Greas-em Dry Graphite Lubricant #237 Coupler Trip Pin Pliers #240 Double Headed Pin Vise #241 Dual Tool Manual Uncoupling Tool and Spring Pick #246 Tap (2-56) and Drills (#50 and #43)