Boston Gear QC721-50-B5-J - 55558-OLD

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Conveying Systems
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  • Industrial Chain Conveyor Components
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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
  • All
Grease
  • All
Grid Couplings
  • All
Locking Assemblies & Shrink Discs
  • All
Rigid Couplings
  • All
Shaft Guards
  • All
Torque Limiters/Torque Overload Devices
  • All
Torsionally Soft Couplings
  • All
AC Motors - NEMA
  • All
  • 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
  • All
  • Definite Purpose Motors
  • General Purpose Motors
  • Washdown Motors
DC Motors
  • All
  • Explosion Proof Motors
  • General Purpose Motors
  • Low Voltage Motors
  • Metric Motors
  • SCR Motors
  • Sub-Fractional Motors
  • Washdown Motors
Gearmotors
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  • AC Gearmotors
  • DC Gearmotors
HVAC/R Motors
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Motor Accessories
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Centrifugal Blowers
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Draft Inducer Blowers
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Centrifugal Fans
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Axial Fans
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Crossflow Blowers
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Inline Gearboxes
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Parallel Shaft Gearboxes
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Precision Gearboxes
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Right Angle Gearboxes
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  • Helical Hypoid
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  • Bevel
  • Worm
Shaft Mount Gearboxes
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Gearbox Parts & Kits
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Custom Gearbox Solutions
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Conveyor Components
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  • Bucket Elevator Components
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Drop Forged Chain
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Engineered Steel Chain
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  • Elevator Chain
  • Welded Steel Chain
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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Belt Drives
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  • Adjustable Motor Bases
  • Belt Drive Accessories
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  • Synchronous Drives
  • V-Belt Sheaves
Bushings
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  • Q-D Bushings
  • Shaft Mount Taper Bore Bushings
  • Split Taper Bushings
  • Taper Bore Bushings
Mechanical Clutches
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  • Mechanical Cam Clutches
  • Torque Overload Devices
Tighteners & Idlers
  • All
  • Drive Tighteners
  • Flat Face Idlers
  • Gear Idlers
  • Gearbelt Pulley Idlers
  • Idler Bushings
  • Sprocket Idlers
  • Tightener Shafts
  • V-Belt Idlers
Open Gearing
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Farm Solutions
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  • Non PTO Products
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Condition Monitoring Systems
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Load Bank
  • All
Switchgear
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Transfer Switches
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Reliability Services and Condition Monitoring
  • All
Coupling Recertification
  • All
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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Product Selectors
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Calculators
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Product Configurators
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The Dealer Toolbox
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V-Belt Drive Kits
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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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Materials Compliance
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Events
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News
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Regal Rexnord Insights
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Training
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Service Center Locations
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Website Help
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<span class="border-bottom pb-1 nav-all-link">All Mounted Bearings</span>
  • All
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
  • All
Self-Aligning Ball Bearings
  • All
Spherical Roller Bearings
  • All
Tapered Roller Bearings
  • All
Thrust Ball Bearings
  • All
Thrust Roller Bearings
  • All
<span class="border-bottom pb-1 nav-all-link">All Specialty & Plain Bearings</span>
  • All
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>
  • All
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>
  • All
Straight Running
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Side Flexing
  • All
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
  • All
Frame Support & Levelers
  • All
Other Conveyor Solutions
  • All
Mounted Ball Bearings
  • All
<span class="border-bottom pb-1 nav-all-link">All Metal Wire Mesh Belts</span>
  • All
Straight Line Positive Drive
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Boston Gear QC721-50-B5-J - 55558-OLD

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Product Specifications

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General Specifications

UPC: 781711428207 Weight: 36.10 LB
HTC: 8483.40.5010 Country of Origin: United States of America

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