A300 Half Rack Long Base
Model 3105 (8’ Half Rack Long Base) and Model 3106 (9’ Half Rack Long Base)
MORE TRAINING OPTIONS THAN ANY OTHER RACK.
PURE RESISTANCE TECHNOLOGY™
LOW-INERTIA DESIGN MAKES IT MORE VERSATILE.
PRT uses ultra-light components and pneumatic resistance. With almost no mass, inertia, or momentum, you can move as fast as you want — without throwing it or slowing it.
The Keiser Advantage
Keiser PRT
Conventional Iron

Strength


Power


Speed

Less inertia, more options.
Iron is effective for strength. PRT is just as effective for strength — and more effective for speed and power.
More effective at faster tempos to improve velocity and power.
Just as effective at slower tempos
to improve strength.
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Mix iron and PRT to optimize inertia.
Dial inertia up or down by changing the ratio of iron and PRT — giving you a level of control that maximizes your training and rehabilitation options.
HIGH INERTIA
CONVENTIONAL IRON-ONLY
Train with traditional iron plates on a barbell, just like any other rack. Full inertia makes it a great option for traditional strength training.
Example
Olympic Bar:
45 Lbs
Mass (Iron):
180 Lbs
Keiser PRT:
0 Lbs
Total:
225 Lbs
HYBRID INERTIA
CONVENTIONAL IRON + KEISER PRT
Mix iron plates with Keiser PRT to fine-tune inertia — driving peak power, orthopedic benefits, adaptation, and variability.
Example
Olympic Bar:
45 Lbs
Mass (Iron):
90 Lbs
Keiser PRT:
90 Lbs
Total:
225 Lbs
LOW INERTIA
KEISER PRT-ONLY
Use Keiser's Pure Resistance Technology with the Keiser Lightweight Bar. Minimal inertia lets you train with more speed, power, and control.
Example
Keiser Lightweight Bar:
6 Lbs
Mass (Iron):
0 Lbs
Keiser PRT:
219 Lbs
Total:
225 Lbs
CONNECT TO KEISER PRT
CONNECT WITH ENDLESS TRAINING OPPORTUNITIES
Mixed Resistance
Keiser Collars
Place Keiser Collars on a standard barbell to use iron and Keiser PRT together.
Standalone PRT
Keiser Lightweight Bar
Use the six-pound Keiser Lightweight Bar to connect directly to Keiser PRT for lowest inertia.
PROGRESSIVE INERTIA
A NEW DIMENSION OF VARIABILITY
Adjust inertia to vary the load, break training plateaus, and drive new adaptation. When progress stalls, variable inertia gives you another way forward.
CONTINUUM OF INERTIA
A LARGER TOOLBOX FOR FORCE, POWER, AND VELOCITY
At high velocities, Keiser PRT is your best option. As loads increase and velocities slow, you have more choices: mass-only, mixed resistance, or PRT-only — each offering different opportunities. Changing the mix may optimize peak power output, orthopedic benefits, and adaptation.
DON’T NEED PRT ON ALL RACKS?
Keiser’s Racks without Air give you a look that matches the styling of our PRT-equipped racks with many of the same features and accessories.
Easy leasing available.
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Questions?
DYNAMIC FUNCTIONAL RESISTANCE
LOW-INERTIA RESISTANCE. CONSISTENT MUSCLE ACTIVATION.
Keiser’s Dynamic Functional Resistance (DFR) provides even resistance through the entire range of motion for more complete muscle activation.
EVEN LOADING ACROSS THE RANGE OF MOTION
Inertia and momentum distort iron’s resistance curve, peaking early and fading as the lift continues. As you move faster, the problem becomes more severe. Keiser’s DFR eliminates those effects with a flat resistance curve — delivering more muscle activation through the entire range of motion.
Unleash Athlete Intent
Train with max velocity through the full range of motion.
With very low inertia and momentum, there’s no need to decelerate at the end of the lift. Keiser PRT lets athletes apply full force and velocity through the entire concentric phase — building even greater power where they’re strongest.
Guided Tour
Explore Keiser Racks
Discover how easy it is to take advantage of the unique versatility of the Keiser’s Pure Resistance Technology.
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FUNCTIONAL VERSATILITY
EXPAND YOUR FUNCTIONAL TRAINING PLAYBOOK.
Connect PRT cables to bars and other accessories to unlock a broader range of functional movements and training styles.
SEE WHAT OTHER RACKS CAN’T DO
Continuous Belt Squat Jump
Alternating Incline Bench Press
Shoulder Press
Belt Forward Lunge
Cable Chop
Push Press
Back Squat
Assisted Pull Up
Belt Squat
Continuous Squat Jump with Bar
DEVELOP SPEED AND POWER ACROSS A WIDER RANGE OF MOVEMENTS.
PRT’s low inertia makes fast, dynamic movements easy to load — opening up a much broader range of functional training on a rack.
Attach cables to the Keiser Lightweight Bar or a wide range of Infinity accessories.
Apply resistance from below, or from above with the Pulley Assist Station (optional).
Train jumps, pulls, presses, and rotational movements for explosive speed and power.
INFINITY ACCESSORY KIT
Model 300824
Get the maximum from your Infinity machines in a cost-effective package. Accessory kit includes Thigh Strap, Waist Belt, Triceps Rope, Ankle Strap, Back/Lat Strap, Cable Handle, and Chop Bar.
SHOCK LOADING
USE INERTIA WHEN IT MATTERS. REDUCE COLLATERAL DAMAGE WHEN IT DOESN’T.
Keiser PRT is as effective as iron when training for strength — but lets you manage orthopedic cost of training in ways iron can’t.
Train with more PRT
to reduce shock loading that can damage joints, muscles, and connective tissue over time.
Train with more mass when you need the unique adaptations that come with more inertia.
Easy leasing available.
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Questions?
OPTIMIZED RESISTANCE
CHOOSE THE PRECISE RESISTANCE FOR YOUR GOALS.
With PRT, set resistance anywhere from 0–200 lbs (0–91 kg) in increments as small as one pound or kilogram with digital accuracy.
Convenient thumb buttons and foot pedals make it easy to adjust resistance up or down — even while lifting.
RESISTANCE CONTROL
ECCENTRIC AND ISOMETRIC OVERLOAD MADE EASY
Control buttons allow a spotter to change PRT resistance instantly — even mid-exercise. Foot pedals can give athletes the same control on their own.
FAST PROGRESSIVE OVERLOAD
RAPID PROGRESSIVE OVERLOAD IN SMALLER INCREMENTS
PRT’s one-pound increments let you keep progress moving forward with finer adjustments. That means smoother progression without stalls — and optimized resistance on good days and bad.
Accommodating Resistance
Quantify and prescribe added resistance with precision.
Bands and chains can’t tell you how much load you’re adding. Keiser PRT lets you prescribe and track it — with measurable accuracy.
ASSISTED RESISTANCE
PRECISE ASSISTANCE YOU CAN QUANTIFY
Keiser PRT lets you apply exactly the assistance needed for success — then track and reduce it in small increments as strength improves.
GROUP TRAINING
LESS TIME CHANGING PLATES, MORE TIME TRAINING
Stop losing time by adding and removing plates for each participant. Load a standard amount of weight for all participants, then use PRT to quickly adjust the precise resistance for each participant.
Easy leasing available.
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Questions?
A300 TECHNOLOGY
Test.Track.Motivate.
Real-time Feedback
Motivate users with data that indicates their level of effort during training and rehabilitation.
Rep Counter
The Power Display makes exercise easier by keeping track of your reps for the current set.
Power Metrics
See your peak power for the set and the percentage of peak power for each rep in real time.
Maximum Power Testing
The Power Display can tell you the resistance level at which you generate the most power with a six-repetition test. This can be an important new metric in any power or velocity program.
BENCH DISPLAY
Maximize performance
with real-time, visual feedback.
Research indicates real-time visual feedback may increase athlete intent. That’s why Keiser’s A300 racks include a display that can be read while benchpressing.
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A300 Half Rack Long Base
ENGINEERED TO PERFORM. BUILT TO LAST.
Innovative engineering. Solidly reliable. And simply more versatile.
Proven Durability. Lowest Cost of Ownership over time.
Made in U.S.A. with domestic and globally sourced material.
AVAILABLE IN TWO SIZES
The A300 Half Rack Long Base comes in two sizes: A standard rack designed to fit under a 9’ ceiling, and a shorter version designed to fit under an 8’ ceiling. Heights do not include accessories. Use of one of our inserts will add 1.5” to height.
A300 8’ Half Rack Long Base (Model 3105): 7’8” (2337 mm)
A300 9’ Half Rack Long Base (Model 3106): 8’8”” (2642 mm)
Features
Specifications
Allows training at any speed, from controlled to explosive, for improved power
Unique hybrid design combines smooth Keiser Pure Resistance Technology™ and free weight resistance to emphasize not only strength training but also speed and stability training
All in one system to accomplish more in less space
Customizable workouts for all users
A rack to fit every need
Dual displays to satisfy both user and trainer
ADA compliant - Section 44 Disabled Access Tax Credit
Model 3105 Height:
92” / 2337 mm
Model 3105 Width:
71” / 1803 mm
Model 3105 Depth:
93” / 2362 mm
Model 3105 Weight:
713 lbs / 323 kg
Model 3105 Resistance:
0 - 200 lbs / 0 - 91 kg
Model 3106 Height:
104” / 2642 mm
Model 3106 Width:
71” / 1804 mm
Model 3106 Depth:
93” / 2362 mm
Model 3106 Weight:
724 lbs / 328 kg
Model 3106 Resistance:
0 - 200 lbs / 0 - 91 kg
CUSTOMIZE EQUIPMENT
MAKE IT MATCH. MAKE IT YOURS.
Customize your order with your logo and paint and upholstery colors — and even thread colors.
DESIGN YOUR IDEAL RACK.
Choose colors, apply your logo, and select accessories with the Keiser Equipment Configurator .
Easy leasing available.
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Questions?
A300 Half Rack Long Base
ADD FUNCTIONALITY WITH OPTIONAL ACCESSORIES
Pull-up Handles
PN: 310820 (set of two handles)
Pulley Assist Station
PN: 310837 (8’), 310838 (9’)
Squat Handles Set (1 Pair)
PN: 310803
Dip Station
PN: 310804
Lightweight Bar
PN: 310805
Technique Tray Set (One Pair)
PN: 310847
Landmine
(sold separately) PN: 310851 (L), 310852 (R)
Adjustable Bench
PN: 3150
Bumper Storage Rack
PN: 310859
PLATFORMS THAT PERFORM
DESIGN, MATERIALS, AND WORKMANSHIP THAT LASTS
PLATFORM INSERT AND 6' LIFTING PLATFORM
FOR A300 HALF RACK LONG BASE
PN: 3176
PLATFORM INSERT
FOR A300 HALF RACK LONG BASE
PN: 3174
Our low-profile platforms are only 1 1/2” thick. They’re made of a 3/4” marine-grade plywood base topped with 3/4” Hardwood maple tongue-and-groove flooring. We seal it to prevent moisture absorption. It’s finished with a two-part finish for commercial floors such as basketball courts. Our specially-formulated impact absorbing rubber is the reason our platforms can be so thin.
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