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DEFS Muddable J-Bead

Designed to cover the raw edges of drywall board

For use in Direct-Applied Exterior Finish Systems (DEFS).

Application(s): DEFS

Designed to protect the raw edges of the board in Direct-Applied Exterior Finish Systems (DEFS). Large perforations allow the base coat mixture to easily flow through and bond to the substrate. Caulk all intersections, butt joints, ends, and corners at the time of installation.

Product Data & Ordering Information

Product code Finish thickness Board thickness (A) Perforated flange (B) Return flange (C) Pcs./Box
MJB50E 1/16" 1/2" 1-1/8" 1/4" 50
MJB58E 1/16" 5/8" 1-1/8" 1/4" 50




ASTM & Code Standards

Product Specifications

  • ASTM D1784 - Standard Classification System and Basis for Specification for Rigid Poly(Vinyl Chloride) (PVC) Compounds and Chlorinated Poly(Vinyl Chloride) (CPVC) Compounds
  • ASTM D4216 (Cell class 13244C) - Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) and Related PVC and Chlorinated Poly(Vinyl Chloride) (CPVC) Building Products Compounds
  • ASTM D638 - Standard Test Methods for Tensile Properties of Plastics
  • ASTM D790 - Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials
  • ASTM D256 - Standard Test Methods for Determining the Izod Pendulum Impact Resistance of Plastics
  • ASTM D648 - Standard Test Methods for Deflection Temperature of Plastics Under Flexural Load in the Edgewise Position
  • ASTM D696 - Standard Test Methods for Coefficient of Linear Thermal Expansion of Plastics Between -30 Degrees Celsius and 30 Degrees Celsius Vitreous Silicia Dilatometer
  • SDS & Product Certification Information

Installation Standards

  • EIFS - ASTM C1397 - Standard Practice for Application of Class PB Exterior Insulation and Finish Systems (EIFS) and EIFS with Drainage
  • DEFS - ASTM C1516 - Standard Practice for Application of Direct-Applied Exterior Finish Systems

Product Submittal Sheets

Click the below Product Code to view Submittal/Tech Datasheet.

Product Code Description
MJB50E, MJB58E DEFS Muddable J-Bead

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