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Trailer hitch receiver, 1-1/4 in square (SAE J684 classes)

What are the dimensions of the Trailer hitch receiver, 1-1/4 in square? · Modern device · basis: Manufacturer specifications (Lippert (CURT))

Also called: 1-1/4 inch hitch receiver, 1-1/4 receiver dimensions, 1-1/4 hitch pin size, 1-1/4 receiver insert, 1-1/4 hitch cover 3d print, 1-1/4 hitch receiver size mm, hitch class chart, sae j684 receiver, hitch receiver sizes, receptor enganche 1-1/4 pulgadas, Anhängerkupplung Aufnahme 1-1/4 Zoll

Exact dimensions. True size, with no printing tolerance added.

length
31.75 mm
width
31.75 mm

Notes

  • A 1-1/4 in receiver takes a 1-1/4 in square shank and a 1/2 in hitch pin, per CURT/Lippert's class and pin guides.
  • Rated weights depend on the specific hitch; the class figures are the maker's typical ranges.
  • No CAD file: the maker publishes only overall sizes, and a plain box or cylinder is not useful design geometry. The table is the published data; parts with real geometry have their own pages.

Trailer hitch receiver, 1-1/4 in square size chart

dimensionvalue
Receiver size1-1/4 × 1-1/4 in (31.75 mm square)
Hitch classesClass 1 (up to 2,000 lb GTW / 200 lb TW) and Class 2 (up to 3,500 lb / 350 lb)
Hitch pin diameter1/2 in (12.7 mm)
Minimum usable pin length (excl. handle)2 in (50.8 mm)

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Lippert (CURT)A Beginner's Guide to Hitch ClasseswebPublisher's page; dimensions are facts
Lippert (CURT)Guide to Hitch Pin SizeswebPublisher's page; dimensions are facts

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

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Plain text: sheet.txt · JSON: /api/geometry?object=trailer-hitch-receiver-1-1-4-inch

Trailer hitch receiver, 1-1/4 in square (SAE J684 classes), isometric render of a generated part
Schematic, not to scale.

Fits with

Trailer hitch receiver, 2 in square (SAE J684 classes), isometric render of a generated part
Trailer hitch receiver, 2 in square (SAE J684 classes)50.8×50.8 mm★ sheet
Trailer hitch receiver, 2-1/2 in square (SAE J684 classes), isometric render of a generated part
Trailer hitch receiver, 2-1/2 in square (SAE J684 classes)63.5×63.5 mm★ sheet
Trailer hitch receiver, 3 in square (SAE J684 classes), isometric render of a generated part
Trailer hitch receiver, 3 in square (SAE J684 classes)76.2×76.2 mm★ sheet

Questions

What pin fits a 1-1/4 in receiver?

A 1/2 in (12.7 mm) pin with at least 2 in usable length.