Specification Brand : CRB CUSTOM ROD BUILDER BulletPoint1 : OPTIMACHOKE CHOKE TUBES - These choke tubes are available in internal and external versions; They are longer and slimmer than conventional Mobilchoke tubes; Thanks to the elongated cone they minimize pellet deformation and improve shot patterns BulletPoint2 : CHARACTERISTICS - The start of the threaded portion of these tubes is located a nominal 50.78mm/2.00" from the breech end of the choke tube; The length of the threaded portion is a nominal 15.9mm/.625"; The major diameter of the thread is 20mm/.787" BulletPoint3 : COMPATIBILITY - OptimaChoke 12Ga Tubes are fully interchangeable on 12 gauge guns with Optima Bore barrels; They are for 12ga guns with the Optima-Choke system only; Fit Beretta 682, Some 687 models, Silver Hawk, DT10, Some 391 models BulletPoint4 : IMPORTANT NOTE - OptimaChoke choke tubes are not interchangeable nor usable with barrels designed for the OptimaChoke HP system; Use of them in barrels designed for use with OptimaChoke HP tubes may result in damage to your barrel and personal injury BulletPoint5 : CONSTRICTIONS - Different choke tube constrictions are available: Full (F), Light Full (FL), Modified (M), Light Modified (LM), Improved Modified (IM), Cylinder (CL), Improved Cylinder (IC), EU Skeet (SK EU), Skeet (SK USA) Color : Black CompatibleDevices : Camera Department : unisex-adult ExternallyAssignedProductIdentifier1 : 0099253000912 ExternallyAssignedProductIdentifier2 : 099253000912 ImportDesignation : Made in the USA or Imported IncludedComponents : item ItemName : CRB Custom Rod Builder Advanced Hand Wrapper System with 2 Spool Holder ItemPackageDimensions_Height : 25.8064 centimeters ItemPackageDimensions_Length : 15.1892 centimeters ItemPackageDimensions_Width : 21.4884 centimeters ItemPackageQuantity : 1 ItemTypeKeyword : gunsmithing-tools-and-accessories Manufacturer : Crb Material : Other MaximumWeightRecommendation : 6 pounds ModelName : OptimaChoke Extended 12Ga Choke Tubes NumberOfBoxes : 1 NumberOfItems : 1 PartNumber : JCOCE05 ProductDescription : This Advanced Hand Wrapper System is a standalone wrapper that provides an upgraded sturdy base and two securely fastened stands with handy precision knobs for quick adjustments — plus, multiple new add-ons to enhance your hand-wrapping experience truly. For example, the all-new ball bearing and spring system eliminates friction for pure, unimpeded thread tension and tight, smooth thread wraps with ease. In the base, the slider allows the thread to track accurately along the wrap, while the stands add two more notches to accommodate wrapping larger diameter rods. The base also includes two convenient insets to keep any guides, tip tops, and tools like guide tubing, and razor blades, and it is more accessible from the first wrap to the last. With the Advanced Hand Wrapping System, you will produce tight, smooth wraps with every rod turn. Please keep it simple and get the job done with two spool options, or upgrade to four spools to let your imagination run wild with fast access to all four different spools at once! ProductSiteLaunchDate : 2020-06-29T01:18:21.689Z Style : Light Modified SupplierDeclaredDgHzRegulation : not_applicable UnspscCode : 45121600