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Custom J-Cup Liners for Synergee J-Hook 3x3 - 5/8" Pin

Custom J-Cup Liners for Synergee J-Hook 3x3 - 5/8" Pin

Superior Barbell Protection with Full Customization Options
J-cup liners designed to provide additional protection for your barbell while giving you the freedom to customize your squat rack.

$44.99
$44.99
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Shipping calculated at checkout.

Includes liners for two J-cups

Fits: Synergee J-Hook 3x3

Not sure which version you have? Check the compatibility guide below.

Choose your design: Single Color

We'll email you a proof of your design before it goes into production.

Archivo Black
  • Archivo Black
  • Bungee
  • Comic Sans
  • Fredoka
  • ORBITRON
  • Russo One
Max 11 characters for Horizontal, 19 for Vertical
Vertical
  • Vertical
  • Horizontal
Max 11 characters for Horizontal, 19 for Vertical
Vertical
  • Vertical
  • Horizontal

The color selected for American Flag Liners is the color behind the flag, and the color of the other liner(s).

Made to order in Texas. Please allow up to 2 weeks for production before shipping. 

We respect intellectual property and reserve the right to decline and refund designs at our discretion.
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Before
After

Representative J-Cup. Fit varies by J-Cup.

More than a replacement liner

Mammoth J-Cup Liners do more than replace worn-out liner material. Extended coverage beneath the front lip helps keep your barbell's knurling from contacting bare steel when the bar contacts the front of the J-cup while racking.

Pick from a variety of customization options

Examples shown on representative J-Cup models. Fit and liner shape vary by J-Cup.

  • Single Color

    Pick one color for a clean simple look.

  • Preset Options

    Choose from one of our ready to order designs

  • Custom Text

    Add your own text, slogan, name, or identifier

  • Custom Logo

    Upload your own logo for maximum customization

How do they compare?

Feature Mammoth Upgrades TPU Liner Standard UMHW Liners*
Material Strength 68D Rigid Plastic
Impact Response Flexible Ridged
Front-lip coverage ✓ ✕
Color Options ✓ ✕
Customization ✓ ✕

*Stock liner specifications vary by manufacturer. UMHW characteristics represent industry averages.

Install in minutes

  1. Unscrew bolts on stock liners
  2. Remove stock liners
  3. Put Custom J-Cup Liners in place
  4. Replace bolts and ensure everything is snug
  5. Grab your barbell and start lifting

Make sure you have the right liner

These are designed to work with the Synergee 3x3 J-Hooks. These J-Cups are made for 3x3" racks and have a 5/8" pin.

If you have any questions about compatibility, feel free to email us at support@mammothupgrades.com

J-cup liner FAQs

How long do J-cup liners last?

J-cup liners are wear components. Service life varies with training frequency, barbell knurling, equipment fit, and use. Inspect them regularly and replace them if worn or damaged.

Can I request a color that is not listed?

Color choices depend on the material and filament colors currently available. The selectable colors shown above are the options currently offered for this product.

How long does it take to receive my order?

These liners are made to order in Texas. Please allow up to two weeks for production before shipping. Shipping transit time is separate and shown at checkout.

What is the return policy for customized products?

Customized-order terms are covered by our Return & Refund Policy.

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