Boston Gear 721B-20KT-J4 - W18873-OLD

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Chain Couplings
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Disc Couplings
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Driveshaft Couplings
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Elastomeric Couplings
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  • Jaw and Wrap
  • Tire
Flange Couplings
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Fluid Couplings
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Gear Couplings
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Gear Spindles
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Grease
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Grid Couplings
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Locking Assemblies & Shrink Discs
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Rigid Couplings
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Shaft Guards
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Torque Limiters/Torque Overload Devices
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Torsionally Soft Couplings
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AC Motors - NEMA
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  • Definite Purpose Motors
  • Electronically Commutated Motors
  • Explosion Proof Motors
  • Farm/Agriculture Motors
  • General Purpose Motors
  • HVAC/R Motors
  • Permanent Magnet Motors
  • Pump Motors
  • Severe Duty Motors
  • Special Voltage Motors
  • Variable Speed Motors
  • Washdown Motors
AC Motors - IEC
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  • Definite Purpose Motors
  • General Purpose Motors
  • Washdown Motors
DC Motors
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  • Explosion Proof Motors
  • General Purpose Motors
  • Low Voltage Motors
  • Metric Motors
  • SCR Motors
  • Sub-Fractional Motors
  • Washdown Motors
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HVAC/R Motors
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Axial Fans
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Crossflow Blowers
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Right Angle Gearboxes
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Drop Forged Chain
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Engineered Steel Chain
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Idlers
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Leaf Chain
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Roller Chain
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Silent Chain
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Sprockets & Wheels
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  • <span class="border-bottom pb-1 nav-all-link">All Sprockets and Wheels</span>
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Bushings
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  • Shaft Mount Taper Bore Bushings
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Mechanical Clutches
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  • Torque Overload Devices
Tighteners & Idlers
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  • Drive Tighteners
  • Flat Face Idlers
  • Gear Idlers
  • Gearbelt Pulley Idlers
  • Idler Bushings
  • Sprocket Idlers
  • Tightener Shafts
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Open Gearing
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Farm Solutions
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Condition Monitoring Systems
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Load Bank
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Switchgear
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Transfer Switches
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Reliability Services and Condition Monitoring
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Coupling Recertification
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Custom Conveyor Design
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Gap Walk
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Installation, Repair & Rebuild Services
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Product Cross Reference
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The Dealer Toolbox
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Request a Quote
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Where To Buy
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eCommerce
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A2L Solutions
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Motor Glossary
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Quick Reference Motor Dimensions
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Software Downloads
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IP69K Washdown Solutions
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Bearings IIoT
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Product Information Portal
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News
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Regal Rexnord Insights
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<span class="border-bottom pb-1 nav-all-link">All Mounted Bearings</span>
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Mounted Ball Bearings
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Mounted Spherical Roller Bearings
  • All
Mounted Tapered Roller Bearings
  • All
Mounted Sleeve Bearings
  • All
<span class="border-bottom pb-1 nav-all-link">All Unmounted Bearings</span>
  • All
Angular Contact Ball Bearings
  • All
Cam Followers
  • All
Cylindrical Roller Bearings
  • All
Deep Groove Ball Bearings
  • All
ER Ball Bearings
  • All
Journal Roller Bearings
  • All
Needle Roller Bearings
  • All
Replacement Inserts
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Self-Aligning Ball Bearings
  • All
Spherical Roller Bearings
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Tapered Roller Bearings
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Thrust Ball Bearings
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Thrust Roller Bearings
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<span class="border-bottom pb-1 nav-all-link">All Specialty & Plain Bearings</span>
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Rod Ends
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Spherical Plain Bearings
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Aerospace
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Composite
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<span class="border-bottom pb-1 nav-all-link">All Bearing Parts & Kits</span>
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Housings
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Seals
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Threaded Covers
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End Caps
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Adapters
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Lock Collars
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Back Side Shields
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Take-Up Frames
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Installation Tools
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Bearing Parts
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<span class="border-bottom pb-1 nav-all-link">All Plastic Modular Chain and Belt</span>
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Straight Running
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Side Flexing
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Spiral Cage Belts
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<span class="border-bottom pb-1 nav-all-link">All TableTop Chains</span>
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Straight Running
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Side Flexing
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Engineered Steel Chain
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Leaf Chain
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Roller Chain
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TableTop® and MatTop® Sprockets
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Industrial Chain Sprockets
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Traction Wheels
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<span class="border-bottom pb-1 nav-all-link">All Conveyor Components</span>
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Product Guide & Brackets
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Curves, Straight Tracks, & Return Systems
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Frame Support & Levelers
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Other Conveyor Solutions
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Mounted Ball Bearings
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<span class="border-bottom pb-1 nav-all-link">All Metal Wire Mesh Belts</span>
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Straight Line Positive Drive
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Boston Gear 721B-20KT-J4 - W18873-OLD

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Product Specifications

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General Specifications

UPC: 781711428207 Weight: 26.10 LB
HTC: 8483.40.5010 Country of Origin: United States of America

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