12-Month Product Warranty on all PRO Sleeves
Maximum stiffness, high-density knee sleeves for powerlifting, strongman, and competition-level squats.
STIFF KNEE SLEEVES PRO: Designed for maximum compression and stability during heavy lifts. Ideal for athletes who want a locked-in feel and strong rebound under load.
MATERIAL: High-density Closed-cell CR Neoprene with reinforced stitching for durability and shape retention.
SLEEVE HEIGHT: 30cm
SIZING: S - XL
DESIGNED FOR: Powerlifting, heavy squats, strength-focused training, and maximal lower-body lifts.
Mammal Strength Stiff Knee Sleeves PRO are built for maximum joint stability, compression, and support under extreme loads, delivering competition-level performance and rebound for powerlifting, strongman, and heavy strength training.
Key Benefits:
Ultra-stiff neoprene construction delivers maximum knee support under heavy loads. High-compression fit helps stabilise the knee joint during squats and maximal lifts. Designed to provide rebound and confidence out of the bottom position. Maintains joint warmth and rigidity throughout heavy sessions. Built for durability and repeated high-intensity training.
Who For:
Powerlifters, strongman athletes, and advanced strength athletes lifting at high percentages. Ideal for those who prioritise maximum support and stability over mobility. Best suited for heavy squats, max-effort lifts, and competition-style training.
How To Use - KEY STEPS:
Please Note - IMPORTANT:
Specs:
All Mammal Strength sleeves are covered by 12-MONTH warranty from the date of purchase.
This warranty covers defects in materials or workmanship under normal training use. It does not cover damage caused by misuse, incorrect sizing, improper care, or normal wear and tear from heavy training.
If you believe your product is faulty, contact our support team with your order number and photos - we’ll always aim to put it right.
Free tracked shipping when you spend over £40.00
24HR Tracked: Next day delivery (order before 11:30am)
Standard Tracked: 2-4 working days
Not quite right? No worries. We offer hassle-free returns within 30 days of purchase.
To start a return or exchange, visit https://mammalstrength.co.uk/a/returns
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Mammal Stiff Knee Sleeves PRO deliver ultimate compression and rebound for maximal lifts. Built with thicker, denser construction than our standard sleeves, designed for powerlifting and strongman work where minimal give matters most.
Built for powerlifters, strongman competitors, and experienced strength athletes training at maximum intensity. If you're chasing PRs and need the least possible flex under the heaviest loads, this is for you.
Fold the sleeve in on itself, pull it up past your calf to just below the kneecap, then unfold it up over your knee. Allow 2-3 sessions for the denser material to break in and mould to your knee shape.
Stiff PRO uses a thicker, denser neoprene construction for maximum rebound and minimal give, built specifically for powerlifting, strongman, and competition-level squats where you want the least amount of flex possible under maximum load.
Yes, more so than our standard sleeves, that's expected given the increased stiffness and density. If you're struggling, fold the sleeve in on itself, pull it up past your calf to just below the kneecap, then unfold it up over your knee.
Due to the increased density of the material, allow 2-3 sessions for your Stiff PRO sleeves to mould to your knee shape, slightly longer than our standard V3 sleeves given the extra stiffness.
Stiff PRO is built for maximal lifts, not high-rep or mobility-focused work. If you need more flexibility for CrossFit or functional training, our 5mm or 3mm Double Ply sleeves are a better fit.
Stiff PRO is designed for experienced lifters training at higher intensities. If you're newer to lifting or don't yet need maximum rigidity, our V3 7mm sleeves offer strong support with more comfort and flexibility.
7mm Knee Sleeves
$83.00
-$108.00
Weightlifting & Heavy Squats
5mm Knee Sleeves
$104.00
Crossfit & Extended Rep Weightlfting
3mm Double Ply Sleeves
$53.00
-$59.00
Functional Training & High-Rep Workouts
Thermal Knee Sleeves
$59.00
-$65.00
Running, Hiking & Endurance Work
Stiff Knee Sleeves PRO
$176.00
-$196.00
Powerlifting, Strongman & 1 Rep Max
Knee Wraps
$41.00
-$45.00
Powerlifting, Max Effort Squats & Strength Training
Mammal Sleeves vs Other Brands
We focus on performance, durability, and real support under load - something most standard gym sleeves simply can’t match.
Maximum joint stability
12-Month Warranty Promise
Built for serious training
Durable performance materials
Trusted by strength and endurance athletes
Standard neoprene
Basic stitching
Generic gym sleeves
Loose compression
0-14 Day Returns
0-6 Months