Guide · Rack pins, band pegs and small hardware
Pins, hitch pins, clevis pins, knobs and magnets: how attachments lock
How J-cups, safeties, dips and landmines lock to a rack, what each maker says about its lock, and what to check before each set.
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Picks that fit
- Synergee J-Cups, pair (2x2, 2x3 or 3x3; 5/8 in or 1 in converter)Check price on Amazon
- Synergee Landmine Attachment (2x2, 2x3 or 3x3; 5/8 in or 1 in converter)Check price on Amazon
- Titan Fitness T‑3 Series Safety Strap Spotter Arms, pair (SKU 402037)Check price on Amazon
Short answer
A weight-bearing attachment should have a lock its maker names: a pin through the upright, hitch pins, a clevis pin, a knob or a magnetic pin. Use exactly the lock the maker shows, check it before each set, and treat any attachment whose maker states no lock with caution. A lock that cannot be fitted means the attachment is not installed.
Picks that fitAll picks and how to choose
Why the lock matters
Most attachments hang on the upright by a pin or hook. The lock is what keeps them from lifting or sliding out when a bar or body pushes on them from an unexpected angle. Makers describe very different locks, and some describe none. Read the maker's wording, not the listing photo.
Pins through the upright
The simplest lock is a pin through the upright that anchors the attachment. REP says its 4000/5000 Series Dip Station attaches like a J-cup into the rack holes and is anchored by a pin.[1] Synergee says its landmine attachment locks into the upright with an included pin.[2]
Hitch pins and detent pins
A hitch pin is a bent spring pin that clips through a hole and over a shaft. Titan's T-3 strap spotter arms lock with two hitch pins per arm.[3] Titan's page does not say whether the hitch pins are included.
Rogue's Monster Safety Spotter Arms 2.0 are secured with a pin through the arm and upright after the arm's mounting pin is rotated down into place, one pin per arm as shown in the manual.[4]
Clevis quick-release pins
A clevis pin has a head on one end and a hole or clip on the other. REP builds its Flip-Down Safeties from 11-gauge steel and locks them with a clevis quick-release pin.[5] REP's page does not confirm the pin is in the box.
Knobs
A knob clamps the attachment against the upright. Synergee's J-cup manual shows an adjustment knob installed on the cup for both 5/8 in and 1 in holes.[6]
Not every knob is a lock. Rogue says the tool-free knurled knob on its Monster Landmine 2.0 has no locking feature and must be checked before each use.[7] Rogue's page states no load rating for that landmine, so we explain it but do not pick it.
Magnetic pins
A magnetic pin holds itself in the hole with a magnet in its head. Bells of Steel lists included quick-locking mag pins on the Manticore version of its Sandwich J-cups; its Hydra and 2.3 in versions state no locking method.[8]
Oak Club sells its MagPin 3 in 1 in and 5/8 in shaft sizes.[9] Its own limits are clear: MagPins are for experienced lifters only, and users should check installation before each lift and always use a failsafe method of attachment securement.[9]
Strap hangers
Rogue's Monster strap manual says to make sure each hanger's pin notch is fully seated on the upright wall and that all rigging must be inspected before each use.[10]
Summary
| Attachment | Lock | Maker wording |
|---|---|---|
| REP 4000/5000 Dip Station | Pin | "anchored by a pin"[1] |
| Synergee landmine | Included pin | locks into the upright with an included pin[2] |
| Titan T-3 strap spotter arms | Hitch pins | two per arm[3] |
| Rogue Monster Safety Spotter Arms 2.0 | Pin through arm and upright | one pin per arm as shown in the manual[4] |
| REP Flip-Down Safeties | Clevis quick-release pin | as listed[5] |
| Synergee J-cups | Adjustment knob | installed for 5/8 in and 1 in holes[6] |
| Rogue Monster Landmine 2.0 | Knurled knob | "no locking feature"; check before each use[7] |
| Bells of Steel Sandwich J-cups, Manticore | Mag pins | included[8] |
| Oak Club MagPin 3 | Magnet | experienced lifters only; use a failsafe[9] |
Before each set
- Every pin, clip or knob the maker shows is in place.
- Pins pass fully through and any clip or ring is closed.
- Knobs are tight, and you have checked any knob the maker says has no lock.
- Nothing has lifted, rotated or slid since the last set.
If a lock cannot be fitted, stop. Our guide to pins that do not line up covers what to ask the maker.
Attachments with a stated lock
Picks that fit3 products
Synergee J-cups and landmine: choose your upright size (2x2, 2x3 or 3x3 in), and a converter version for 1 in holes.
More on choosing
Titan T-3 strap spotter arms: Titan T-3 racks only. 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)
Landmine sold by upright size, pinned to the upright
Synergee Landmine Attachment (2x2, 2x3 or 3x3; 5/8 in or 1 in converter)
Strap spotter arms for T-3 and 2x3 racks with 11/16 in holes
Titan Fitness T‑3 Series Safety Strap Spotter Arms, pair (SKU 402037)
For Bells of Steel racks, the maker's own magnetic pins come in one version per hole class:
Picks that fit2 products
MAG-PIN-HDR for Hydra (5/8 in holes), PIN-MAG-MTC for Manticore (1 in holes). Sold singly; Bells of Steel states no load rating for these pins.
Magnetic pin for Hydra racks (5/8 in holes)
Magnetic pin for Manticore racks (1 in holes)
Next
Questions
Do J-cups need a locking pin?
Follow the maker. Some J-cups state a lock, such as the mag pins Bells of Steel includes with its Manticore Sandwich J-cups or the adjustment knob in Synergee's manual; others state none. If the maker shows a lock, use it every time.[8][6]
Are magnetic pins safe?
We cannot rate them. Oak Club says its MagPins are for experienced lifters only and tells users to check installation before each lift and always use a failsafe method of attachment securement.[9]
What is a clevis pin?
A pin with a head on one end and a cross-hole or clip on the other, held in place by a spring clip or ring. REP locks its Flip-Down Safeties with a clevis quick-release pin.[5]
What should I check before each set?
That every pin, knob or clip the maker shows is in place and fully seated. Rogue's strap manual says to make sure each hanger's pin notch is fully seated and that all rigging must be inspected before each use.[10]