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  1. Trailer Door Hinges
  2. Redline
  3. Hinge Pin
  4. Build Your Own Hinge
  5. Greasable Pin
  6. 4-1/2 Inch Long
1/2" Diameter Greasable Hinge Pin, 4-1/2" Long

1/2" Diameter Greasable Hinge Pin, 4-1/2" Long

Item # HP412G
Our Price: $12.78
Trailer Door Hinges
Shipping Weight: 0.25 lbs
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Hinge pins are welded to either the outer frame or the gate/door and then inserted into the welded hinge pin nipples to create custom, heavy-duty hinges. Greasable pins feature a grease zerk for lubrication. Great Prices for the best trailer door hinges from Redline. 1/2" Diameter Greasable Hinge Pin, 4-1/2" Long part number HP412G can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (1)
  • Q & A (0)
  • Videos (1)
  • Photos

Redline Trailer Door Hinges - HP412G

  • Hinge Pin
  • Build Your Own Hinge
  • Greasable Pin
  • 4-1/2 Inch Long
  • 1/2 Inch Diameter
  • Weld-On
  • Redline

Hinge pins are welded to either the outer frame or the gate/door and then inserted into the welded hinge pin nipples to create custom, heavy-duty hinges. Greasable pins feature a grease zerk for lubrication.


  • Build your own hinge
  • Great for trailers and agricultural applications


  • Outer diameter 1/2"
  • 4-1/2" long

HP412G, Hinge Pin Greasable 1/2" OD 4 1/2" Long

Video of 1/2" Diameter Greasable Hinge Pin, 4-1/2" Long

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Redline Enclosed Trailer Parts - Doors - HP412G Review

Today were going to review part number HP412G. This is the Redline 1/2-inch diameter Greaseable Hinge Pin. This hinge pin is welded to either the outer frame of the trailer or the gate and door and then this is inserted into the welded hinge pin nipple to create a custom heavy duty hinge. This is used when building your own hinge, its great for trailers and agriculture applications. This is a grease-able hinge pin which means it has a Zerk fitting right here on the very end and basically what that means is you can attach your grease gun to the end of this fitting and pump grease into the inside which will come out this hole right here and spread all along the length of the hinge pin which will lubricate the total hinge. Ill give you a few measurements on this, total length of this pin is 4-1/2 inches, the outer diameter is going to be a 1/2 inch.

And that should do it for a review on part number HP412G.

Customer Reviews

1/2" Diameter Greasable Hinge Pin, 4-1/2" Long - HP412G

Average Customer Rating:  5.0 out of 5 stars   (1 Customer Reviews)

Hinge pins are welded to either the outer frame or the gate/door and then inserted into the welded hinge pin nipples to create custom, heavy-duty hinges. Greasable pins feature a grease zerk for lubrication.


Ordering was simple, part was exactly what I needed. Actually received part before I expected, always a good thing!


See what our Experts say about this Redline Trailer Door Hinges

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    Image 1 for
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    Image 1 for
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Info for this part was:

Employee Robert G
Expert Research:
Robert G
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Jeff D
Installed by:
Jeff D

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