Buying task · J-cups and J-hooks
J-cups and J-hooks: upright size, pin size and the maker's rating
How to choose J-cups or J-hooks for your rack: upright size, 5/8 in or 1 in pin, the maker's host list, the rating's scope, the lock and the liner.
We may earn a commission if you buy through links on this page. How we make money
Short answer
Choose J-cups whose maker lists your rack, or your exact upright size and hole size, then read the load rating in the maker's own scope. Upright size alone is not enough: Rogue sells separate 1 in and 5/8 in pin versions of the same Ghost Roller J-cup for its Monster and Monster Lite racks, which share 3x3 in tubing.[1]
What J-cups do and why fit is narrow
A J-cup (Titan says J-hook) hangs on the rack's upright and holds the bar between sets. It touches the rack in three places: it wraps the tube, its pin goes into a hole, and its lock keeps it from lifting out. Each of those has its own number, and makers set each one per rack line.
That is why one maker's cups can be sold in several versions for one tube size. Rogue says its Infinity J-cups use a 5/8 in pin and fit only its 2x3 in Infinity and R-Series units.[2] REP makes its 1000 Series standard J-cups for 2x2 in uprights with 1 in pins and lists the PR-1000, PR-1050 and PR-1100,[3] while its round sandwich J-cups are made for 3x3 in 4000 Series uprights with 5/8 in pins.[4] Powertec says its Premium J-hooks fit only Powertec racks with 2 3/8 in uprights and a 1 in peg.[5]
The decisions, in order
1. Upright size. Measure the outside of the tube and compare it with the rack maker's figure. 2x2, 2x3, 3x3 and 60 mm tubes all exist, and a 2x3 tube has two faces of different widths. The measuring guide shows how.
2. Pin class: 5/8 in or 1 in. The same 3x3 tube is sold with both. Bells of Steel sells separate Sandwich J-cup pairs for 3x3 Hydra racks with 5/8 in holes and 3x3 Manticore racks with 1 in holes, plus a pair for 2.3 in racks with 5/8 in holes.[6] Titan states a 5/8 in pin for its T-3 J-hooks.[7] See 5/8 in vs 1 in rack hardware.
3. The cup maker lists your rack. REP says it cannot guarantee its parts fit non-REP racks because of machining differences.[8] When a maker gives a condition instead of a list, keep both parts of it: Bells of Steel says the Hydra version of its standard J-cups fits non-Bells of Steel racks with true 3x3 in uprights and 5/8 in holes.[9]
4. The rating and its scope. Synergee rates a pair of its J-cups at 750 lb combined with both cups at equal heights.[10] Bells of Steel lists 1,000 lb combined for its Hydra and Manticore Sandwich J-cups and 880 lb combined for the 60 mm version.[6] REP lists 700 lb rackable capacity for its 1000 Series standard cups[3] and 1,000 lb for its Round Sandwich cups,[4] without saying per cup or per pair. Quote the number the way the maker writes it; the load ratings guide explains the terms.
5. The lock. Synergee's manual shows an adjustment knob fitted for both 5/8 in and 1 in holes.[11] Bells of Steel states a lock (included magnetic pins) only for its Manticore Sandwich J-cups.[6] One reviewer found Titan T-2 roller J-cups fit a REP PR-1100 but their lock-in pins could not be used as intended.[12] If your lock does not line up, read when the locking pin does not line up.
6. Style and liner. Standard, sandwich and roller cups differ in how the bar sits and slides. Synergee lists a 3.4 in shelf on its 3x3 cup and 3.3 in on its 2x2 and 2x3 versions.[10] Rogue offers its Ghost Roller J-Cups 2.0 with composite or coated steel rollers and lines them with UHMW.[13]
How to choose
Start with your upright and hole size, then pick a maker that names both. Three approved pairs state their size and rating. Synergee sells 2x2, 2x3 and 3x3 versions with a metal converter for 5/8 in or 1 in holes;[10] confirm the converter is in the version you select. Titan's T-3 J-hooks are for T-3 racks with a 5/8 in pin.[7] Fringe Sport's 3x3 pair is for 1 in holes and names Rogue Monster, REP PR-5000 and Titan TITAN Series racks.
Picks that fit3 products
Synergee: choose your upright (2x2, 2x3 or 3x3) and, for 1 in holes, a version with the 5/8 in / 1 in converter (JHOOKC); the NC versions take 5/8 in holes only.
More on choosing
Titan: the T-3 Series J-Hooks pair is for T-3 racks only. Fringe Sport: the 3x3 pair is for 1 in holes. On Amazon, check that 'Ships from / Sold by' shows 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)
Choose the Titan T-3 J-Hooks for a Titan T-3 rack
Fringe Sport J-Cups 3x3 pair, 1 in holes (JCUP‑FS‑3x3‑Black)
Every page on J-cups
Guides
- Standard vs sandwich vs roller J-cups
- J-cups for 2x2 and 2x3 uprights: what the makers list
- J-cups for 3x3 uprights: 5/8 in and 1 in versions
- Rack-brand vs third-party attachments: fit, rating and warranty
- 5/8 in vs 1 in rack hardware: which class your rack uses
- When an attachment's locking pin does not line up
- Rack attachment load ratings: pair, combined and rackable
Tool
Upright sizes
Rack systems
- Rogue: Infinity and R-Series, Monster Lite, SML-2, RML-390F Flat Foot, Monster
- REP: PR-1000 and PR-1050, PR-1100, PR-4000, PR-5000
- Titan: T-2, T-3, X-3, TITAN Series
- Bells of Steel: 60 mm racks, Hydra, Manticore
- Others: PRx Profile, Force USA MyRack, Powertec, Sunny Power Zone
Key terms
Pin diameter, hole diameter, hole converter, standard J-cup, landing zone, per-pair rating, combined capacity and locking pin.
Everything in this topic
Guides
- J-cups for 2x2 and 2x3 uprights: what the makers listHelps owners of 2x2 and 2x3 racks find J-cups whose maker lists their upright, hole and pin size.
- J-cups for 3x3 uprights: 5/8 in and 1 in versionsHelps owners of 3x3 racks pick J-cups in the right pin class with a rating they can read correctly.
- Rack-brand vs third-party attachmentsHelps you weigh a rack maker's own attachment against a third-party one using documented fields, not brand names.
- Standard vs sandwich vs roller J-cupsHelps you choose a J-cup style from what makers actually publish about shape, liner and rating.
Comparisons
- J-cups compared: upright, pin size, liner and ratingHelps you choose between J-cups by the rack they fit first, then by lock and the maker's rating in its own scope.
Shortlists
- J-cups for 2x2 and 2x3 uprights with the pin size statedHelps a 2x2 or 2x3 rack owner pick J-cups made for their tube and hole size, with the rating in the maker's scope.
Common questions
Which of these J-cups fits my rack?
The one whose maker lists your rack or your measured upright and hole size. Titan's fit only the T-3, Sunny's only the Powerzone models Sunny names, and Synergee's any rack whose upright and hole class match a Synergee variant. More in J-cups compared: upright, pin size, liner and rating
Is Synergee's 750 lb rating per cup?
No. Synergee rates a pair at 750 lb combined when both cups are set at equal heights. More in J-cups compared: upright, pin size, liner and rating
Why not the REP, Bells of Steel or Rogue J-cups?
They are not in our approved catalog yet. Their makers' fit and rating details are in our J-cup guides. More in J-cups compared: upright, pin size, liner and rating
Can I compare the ratings directly?
No. Per pair at equal heights, combined and unstated scopes are different measures. Choose by fit and lock first, and read each rating in the maker's own words. More in J-cups compared: upright, pin size, liner and rating
Will Titan T-2 J-hooks fit my REP PR-1100?
Neither maker lists that pairing. Garage Gym Experiment reported that Titan T-2 accessories relying on lock-in pins did not fully work on a PR-1100, so treat it as not compatible unless Titan lists your rack. More in J-cups for 2x2 and 2x3 uprights: what the makers list
Which J-cups fit a 2x3 rack with 11/16 in holes?
Start with the rack maker's own cups. For the Titan T-3, which lists 11/16 in holes, Titan states a 5/8 in pin for its T-3 J-hooks. A third-party cup must list your upright and hole size. More in J-cups for 2x2 and 2x3 uprights: what the makers list
Is Synergee's 750 lb per cup or per pair?
Per pair. Synergee rates a pair at 750 lb combined when both cups are set at equal heights. Do not split it into a per-cup number. More in J-cups for 2x2 and 2x3 uprights: what the makers list
Is a 2x2 rack the same as a 50 mm rack?
No. 2x2 in works out to 50.8 x 50.8 mm, not 50 x 50 mm. More in J-cups for 2x2 and 2x3 uprights: what the makers list
Questions
Do J-cups fit any rack with the same upright size?
No. Rogue says its Infinity J-cups fit only 5/8 in Infinity and R-Series units, even though other racks use 2x3 in tubing, and REP says it cannot guarantee its parts fit non-REP racks. Go by the cup maker's named racks or its stated upright and hole size.[2][8]
Is a J-cup rating per cup or per pair?
It depends on the maker, and some do not say. Synergee rates a pair at 750 lb combined with both cups at equal heights, Bells of Steel uses 'combined' wording, and REP lists a rackable capacity without saying per cup or per pair. Never split a pair rating into a per-cup number.[10][6][3]
Do I need J-cups with a locking pin?
Choose cups whose maker states how they lock or are retained, and use that lock as the manual shows. Synergee's manual shows an adjustment knob for both 5/8 in and 1 in holes; Bells of Steel states included magnetic pins only for its Manticore Sandwich J-cups. If a lock cannot be installed on your rack, stop and contact the maker.[11][6]
What is the difference between J-cups and J-hooks?
Nothing structural: both names describe the hook that holds the bar on the upright. Titan calls its T-3 parts J-hooks, while Rogue, REP and Synergee say J-cups.[7]