Guide · J-cups and J-hooks
J-cups for 3x3 uprights: 5/8 in and 1 in versions
3x3 racks come in 5/8 in and 1 in hardware. Which J-cups REP, Rogue, Bells of Steel, Synergee and Fringe Sport list for each, with every rating in the maker's words.
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Short answer
Find your rack's pin class first: 3x3 in racks come in 5/8 in and 1 in hardware. Then buy the J-cup version made for that class. REP's Round Sandwich and Bells of Steel's Hydra cups are 5/8 in; Rogue's Ghost Roller and Bells of Steel's Manticore cups come in 1 in versions. Quote every rating in the maker's own scope.
Identify the pin class first
The outside of a 3x3 upright does not tell you which pins it takes. Rogue Monster Lite, REP PR-4000 and Bells of Steel Hydra use 5/8 in parts; Rogue Monster, REP PR-5000 and Bells of Steel Manticore use 1 in parts. Our 5/8 in vs 1 in guide lists the maker sources for each.
Also check the tube. A 3 x 3 in upright works out to 76.2 x 76.2 mm, which is 1.2 mm per side larger than a 75 x 75 mm tube.[1] A cup labeled 75 mm is a different size.
5/8 in versions
REP Round Sandwich J-cups. REP says they are made for 3x3 in 4000 Series uprights, use 5/8 in pins and have a dual-lock wraparound C-cup design.[2] REP lists 1,000 lb rackable capacity without saying per cup or per pair.[2]
Bells of Steel Hydra. Bells of Steel sells its Sandwich J-cups in separate pairs, including one for 3x3 Hydra racks with 5/8 in holes.[3] It lists 1,000 lb combined for the Hydra version and states no locking method for it.[3]
Bells of Steel also says the Hydra version of its standard J-cups fits Hydra racks and non-Bells of Steel racks with true 3 x 3 in uprights and 5/8 in holes, with a 1,000 lb combined capacity.[4] That is a statement with two conditions, true 3x3 and 5/8 in holes. It does not name other brands, and it does not cover 1 in or 75 mm racks.
Rogue Ghost Roller, Monster Lite version. Rogue sells a 5/8 in pin version of its Ghost Roller J-Cups 2.0 for Monster Lite units.[5]
1 in versions
Rogue Ghost Roller, Monster version. Rogue sells a 1 in pin version for Monster Series units.[6] It offers composite or coated steel rollers and lines the front, back and lip with UHMW.[7] Neither Ghost Roller page we read lists a load rating, so we attach none.
Bells of Steel Manticore. Bells of Steel sells a Sandwich J-cup pair for 3x3 Manticore racks with 1 in holes, lists 1,000 lb combined, and includes quick-locking mag pins on that version.[3] Bells of Steel also says Hydra attachments fit Manticore racks through the keyholes, though they may lift slightly when pushed upward.[8] That applies to Bells of Steel parts on Bells of Steel racks only.
Third-party: sold by size
Synergee J-cups come in a 3x3 version, with a metal converter so one pair can be set up for 5/8 in or 1 in holes.[9] Synergee also sells versions without the converter, so confirm it is in the variant you choose. Synergee rates a pair at 750 lb combined when both cups are set at equal heights, and lists a 3.4 in resting shelf on the 3x3 cup.[9]
Ratings, in each maker's scope
| J-cup | Pin class | Rating as the maker words it |
|---|---|---|
| REP Round Sandwich (4000 Series) | 5/8 in | 1,000 lb rackable capacity, scope not stated[2] |
| Bells of Steel Sandwich, Hydra | 5/8 in | 1,000 lb combined, basis not stated[3] |
| Bells of Steel Sandwich, Manticore | 1 in | 1,000 lb combined, basis not stated; mag pins included[3] |
| Bells of Steel standard, Hydra | 5/8 in | 1,000 lb combined[4] |
| Rogue Ghost Roller 2.0 | 5/8 in or 1 in | none published[6] |
| Synergee 3x3 | 5/8 in, or 1 in with converter | 750 lb per pair, combined, equal heights[9] |
"Rackable", "combined" and "per pair at equal heights" are different scopes. Do not turn any of them into a per-cup number.
Approved J-cups for 3x3 in uprights
Picks that fit2 products
Synergee: choose a 3x3 in variant, the converter version (JHOOKC-3X3) for 1 in holes or the NC version (JHOOK-3X3-NC) for 5/8 in holes only.
More on choosing
Fringe Sport 3x3 pair: 1 in holes only, for the racks Fringe Sport names (its own 3x3 racks, Rogue Monster, REP PR-5000, Titan TITAN Series). On Amazon, check that Ships from / Sold by is Amazon.com or the brand.
Choose Synergee if your rack is not on any maker's named list
Synergee J-Cups, pair (2x2, 2x3 or 3x3; 5/8 in or 1 in converter)
Fringe Sport J-Cups 3x3 pair, 1 in holes (JCUP‑FS‑3x3‑Black)
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Questions
Which J-cups fit a Rogue Monster Lite?
Rogue sells its Ghost Roller J-Cups 2.0 in a 5/8 in pin version for Monster Lite units and a separate 1 in version for Monster Series units. Choose the 5/8 in version for Monster Lite.[6]
Do Bells of Steel J-cups fit other 3x3 racks?
Bells of Steel says the Hydra version of its standard J-cups fits non-Bells of Steel racks with true 3 x 3 in uprights and 5/8 in holes. Both conditions must hold; it is not a list of approved brands.[4]
Are 1,000 lb J-cups rated per cup?
Usually the maker does not say. REP lists 1,000 lb rackable capacity for its Round Sandwich J-cups without a per-cup or per-pair scope, and Bells of Steel says 1,000 lb combined. Quote the maker's wording and do not split it.[2][3]
Will 75 mm J-cups fit a 3x3 rack?
Not on the label alone. 3x3 in works out to 76.2 mm, 1.2 mm per side larger than 75 mm. Only the attachment maker's stated size or host list can answer it.[1]