Parcel ground shipping
Items weighing 149 lb or less ship by ground parcel rather than freight.
Receive by Sep 22
New
BUILT Strength Infinite Series Back Extension
$3,295.00
Parts & Labor, Plus Lifetime Frame
New equipment. Coverage starts on the date of delivery.
Shipping calculator
Enter your state and ZIP code to see delivery options and prices.
Machine overview
Condition: New
Warranty: 1 Year Parts & Labor (Extended Available)
Returns: 30-Day Returns & Exchanges
Shipping: Driveway Delivery, or Inside Delivery & Assembly
Receive by: Sep 22
How It Ships: Crated w/ Assembly Manual
Delivery options
How delivery works
Your item’s shipping method and price are confirmed in the shipping calculator and at checkout. Here is what each delivery path means.
Driveway freight delivery
Your equipment is palletized and protected. The freight carrier schedules delivery, then uses a liftgate to lower it to your curb or driveway. Moving it inside and unpacking it are up to you.
Inside delivery & assembly
When selected and available for your address, the delivery team brings the equipment into the room, assembles and tests it, then removes the packaging.
Full truckload
For commercial builds and multi-pallet orders, a dedicated trailer keeps the full order together in one delivery. We confirm the unloading plan before the truck ships.
Size: 48" × 39" × 62" tall
Financing: From $174.37/mo or 0% APR with
Check your purchasing powerWhat New Means
Brand new, current-model equipment shipped in the factory crate with the full manufacturer warranty. Extended coverage is available at checkout.
Warranty Coverage
New and remanufactured equipment are both covered for one year, parts and labor, backed by us. Extended protection is available on either through BAG Care+. Used equipment is sold as-is with no warranty coverage, and is described honestly before you buy. We service nationwide - every ZIP code in the country - so coverage travels with the machine.
30-Day Returns & Exchanges
Change your mind within 30 days of delivery and you can return the machine or exchange it for a different size, color or configuration.
Return shipping is the customer's responsibility and a 15% restocking fee applies to preference returns and exchanges. Freight items must go back packaged to the same standard they arrived in — we will tell you exactly what that means before anything is collected.
Anything that arrives damaged or fails under warranty is handled separately and carries no restocking fee. Full terms are in our Returns, Exchange & Refund Policy.
Add before it ships
Before the freight bookingCoverage and accessories have to go on the same booking as the machine. Add them here and they travel together.
Extended warrantyRecommendedEvery machine includes 1 year parts and labor.
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Product details
Commercial-grade equipment, inspected and supported by warranty.
The Infinite Series Back Extension pairs a fixed 45-degree platform with a 200 lb selectorized stack, so you can load the posterior chain far past bodyweight without waiting on plates. Adjustable-height thigh pads set the pivot at the hips for a clean hinge, while quilted leg rollers and thigh pads keep you locked in through every rep.
A D-clip attachment point accepts multiple handle styles — a straight bar is included — for weighted extensions that scale with the athlete, and a bar catch at the bottom keeps the bar within reach between sets. Fixed handlebars at the thigh pads assist entry and exit, and the textured flat and angled platforms deliver no-slip traction on high-traffic commercial floors.
Primary muscles targeted
Erector Spinae Gluteus Maximus Hamstrings
Secondary muscles
Multifidus Quadratus Lumborum
Key features
200 lb selectorized stack
Pin-select resistance loads the posterior chain well beyond bodyweight for progressive strength work without swapping plates.
Adjustable thigh pads
Height-adjustable, quilted thigh pads and leg rollers set the hip pivot precisely and lock the lower body in for a clean hinge.
D-clip attachment system
Swap in multiple handle styles at the D-clip for loaded extensions — a straight bar is included — with a bar catch that keeps it within reach between sets.
No-slip textured platforms
Sturdy flat and fixed angled platforms with textured surfaces deliver secure footing, and fixed handlebars assist safe entry and exit.
Specifications
Dimensions (L × W × H)
48" × 39" × 62"
1219 × 991 × 1575 mm
Weight stack
200 lb
91 kg selectorized
Resistance type
Pin-select stack
Incremental weight changes
Thigh pads
Height adjustable
Quilted pads & leg rollers
Attachments
D-clip · straight bar included
Accepts multiple handle styles · bar catch at base
Frame
11-Gauge (3mm) Steel
1. How do I select weight on a selectorized machine?
Insert the weight pin into the desired stack hole; ensure it clicks into place before use.
2. What weight stack size should I choose?
Most base level weight stacks can accommodate even advanced lifters, but for the real weight-movers, look for the items with expansion stacks.
3. What maintenance is required?
Inspect guide rods and stack alignment monthly; wipe rods and replace worn bushings annually.
4. Is installation available?
Yes—schedule professional installation during checkout for a seamless setup.
5. What warranty covers these machines?
New units carry full OEM coverage; remanufactured units include a 12 month Build A Gym Guarantee.
30-Day Returns & Exchanges
Buy with confidence. Every Build A Gym order includes a 30-day window to return or exchange, whether you want a different size, color or configuration. Return shipping is the customer's responsibility and a 15% restocking fee applies to preference returns; warranty and damage claims carry no restocking fee. Full details in our Returns, Exchange & Refund Policy.
The Infinite Series Back Extension pairs a fixed 45-degree platform with a 200 lb selectorized stack, so you can load the posterior chain far past bodyweight without waiting on plates. Adjustable-height thigh pads set the pivot at the hips for a clean hinge, while quilted leg rollers and thigh pads keep you locked in through every rep.
A D-clip attachment point accepts multiple handle styles — a straight bar is included — for weighted extensions that scale with the athlete, and a bar catch at the bottom keeps the bar within reach between sets. Fixed handlebars at the thigh pads assist entry and exit, and the textured flat and angled platforms deliver no-slip traction on high-traffic commercial floors.
Primary muscles targeted
Erector Spinae Gluteus Maximus Hamstrings
Secondary muscles
Multifidus Quadratus Lumborum
Key features
200 lb selectorized stack
Pin-select resistance loads the posterior chain well beyond bodyweight for progressive strength work without swapping plates.
Adjustable thigh pads
Height-adjustable, quilted thigh pads and leg rollers set the hip pivot precisely and lock the lower body in for a clean hinge.
D-clip attachment system
Swap in multiple handle styles at the D-clip for loaded extensions — a straight bar is included — with a bar catch that keeps it within reach between sets.
No-slip textured platforms
Sturdy flat and fixed angled platforms with textured surfaces deliver secure footing, and fixed handlebars assist safe entry and exit.
Specifications
Dimensions (L × W × H)
48" × 39" × 62"
1219 × 991 × 1575 mm
Weight stack
200 lb
91 kg selectorized
Resistance type
Pin-select stack
Incremental weight changes
Thigh pads
Height adjustable
Quilted pads & leg rollers
Attachments
D-clip · straight bar included
Accepts multiple handle styles · bar catch at base
Frame
11-Gauge (3mm) Steel
1. How do I select weight on a selectorized machine?
Insert the weight pin into the desired stack hole; ensure it clicks into place before use.
2. What weight stack size should I choose?
Most base level weight stacks can accommodate even advanced lifters, but for the real weight-movers, look for the items with expansion stacks.
3. What maintenance is required?
Inspect guide rods and stack alignment monthly; wipe rods and replace worn bushings annually.
4. Is installation available?
Yes—schedule professional installation during checkout for a seamless setup.
5. What warranty covers these machines?
New units carry full OEM coverage; remanufactured units include a 12 month Build A Gym Guarantee.
30-Day Returns & Exchanges
Buy with confidence. Every Build A Gym order includes a 30-day window to return or exchange, whether you want a different size, color or configuration. Return shipping is the customer's responsibility and a 15% restocking fee applies to preference returns; warranty and damage claims carry no restocking fee. Full details in our Returns, Exchange & Refund Policy.
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Complete the room
The machines our install crew puts in the same room as this one - priced as one shipment, delivered in one booking.
$3,295.00
This machine
Bundle total
- Items
- $5,547.28
- Bundle price
- $5,269.92
- Estimated bundle saving
- −$277.36
- Ships complete in
- 4–6 weeks
One freight booking, one delivery window, one crew. Inside Delivery & Assembly available on the whole bundle.