hammer strength

Ground Base® Jammer

Name: Plate Loaded Ground Base® Jammer
Brand: hammer strength

Built for raw power and explosive performance, the Hammer Strength Ground Base® Jammer is the real deal—no imitations, no compromises. While racks try (and fail) to mimic its movement, only the Jammer delivers the perfect blend of converging and diverging motion, unlocking true athletic drive.

Designed in the ‘90s and still unmatched today, it’s the gold standard for developing force, power, and on-field dominance. When it comes to training like an athlete, there’s no substitute—there’s only the Jammer.

Dimensions (L x W x H): 66 in x 79 in x 83 in (167 cm x 202 cm x 212 cm)

Weight: 370 lb (168 kg)

View All Specs +

Built for Explosive Power

Athletes don’t just lift—they drive, push, and explode. The Ground Base® Jammer trains force production in the most athletic way possible, mimicking the powerful pressing movements seen in sport. Whether it's linemen battling in the trenches or sprinters driving out of the blocks, the Jammer builds the kind of strength that translates to real performance.

Unmatched Since the ‘90s

The Ground Base® Jammer isn’t new—it’s legendary. While other companies try to replicate its movement with half-measures, only Hammer Strength delivers the true Jammer experience. Designed in the mid-90s and still dominating weight rooms today, it remains the ultimate training tool for explosive strength.

Product Configurator

Customize your own Jammer

Customize your equipment like never before with our 3D configurator tool, featuring augmented reality to visualize and drop your design directly into your space.

Specs

Dimensions (L x W x H)	66 in x 79 in x 83 in (167 cm x 202 cm x 212 cm)
Weight	370 lb (168 kg)
Max Load Capacity (per arm)	4 x 45 lb plates (4 x 20 kg plates)

Starting Resistance (per arm)	8 lbs (3.6 kg)
Product Code	GB-J
Storage Weight Horns	6
Recommended Plate Mix	4 x 45 lb plates, 4 x 25 lb plates, 4 x 10 lb plates

FAQ

Rack-mounted press arms may look similar, but they don’t move like a true Jammer. Without independent, converging, and diverging arms, they lack the natural pressing path that builds real-world power. The Jammer was engineered for explosive strength, allowing athletes to drive force through the ground while pressing in an athletic motion—something rack-mounted arms simply can’t match.

Standing presses demand total-body activation. Instead of isolating the upper body, the Plate Loaded Jammer forces athletes to engage their core, legs, and hips to generate force—just like they would in competition. This builds functional power, improves coordination, and transfers directly to on-field performance.

Any athlete who needs explosive power, speed, and strength. Football players use it to build the drive and punch needed for the trenches. Combat athletes use it for powerful strikes. Sprinters and jumpers develop forceful hip extension. Whether it’s contact sports, track and field, or any discipline requiring raw power, the Ground Base® Jammer delivers.

Yes—but they’re not the Jammer. Our Lightning Arms are lightweight yet durable pressing attachments designed for our HD Elite iD, HD Athletic NX, and HD Perimeter systems. They offer versatile pressing options, but for true explosive, ground-driven power, nothing replaces the original Hammer Strength Jammer.