A3 Carbon Steel
Reinforced Steel Body
Won’t bend. Won’t snap. Built to outlast the car you’re fixing.
13,000+
wrenchers who beat the bolt
KnuckleReach 15 - Offset Extension Wrench, 3/8"
KnuckleReach 15 - Offset Extension Wrench, 3/8"
Offset extension wrench · 3/8" drive · chain-driven
15.2" reach
0.7" thin
0° swing arc
Couldn't load pickup availability
What it is — and what it isn't
What it is — and what it isn't
It is an access tool. It reaches past brackets, manifolds and firewalls and turns the bolt while your hands stay fifteen inches away in the open. Rated 53 ft·lb (72 Nm) through the chain, which covers the fasteners that vibrated loose or were torqued to spec.
It is not a breaker bar. A stud rust-welded to an exhaust manifold needs penetrating oil and a breaker bar first. Break it loose, then this does the twenty turns you can't reach.
It is not impact-rated. We don't claim it and we won't sell it that way. Cordless impact on setting 1 or 2 at most, pneumatic at 2 to 3 bar. Hand tools maximise chain life.
Will it fit my gap?
Will it fit my gap?
It needs roughly 0.7" of clearance to slide in, and 15.2" of run back to your hands. If there is a straight path to the bolt, this reaches it.
If the bolt sits around a corner or behind something solid, no offset extension solves that — ours included. Measure first, and use the 60 days if we're wrong.
Specs & materials
Specs & materials
Drive: 3/8" square, both ends
Mechanism: sealed steel roller chain, 1:1 ratio
Body: carbon steel, zinc plated
Length: 15.2" / 386 mm
Thickness: 0.7" / 18 mm
Rotation: 360° bidirectional, 0° swing arc
Rated torque: 53 ft·lb / 72 Nm
Socket retention: spring-loaded steel detent ball
Shipping & returns
Shipping & returns
Ships from a US warehouse within one business day. Delivery in 2 to 5 business days, tracked. You get the tracking number the moment it leaves the shelf.
Sixty days to try it on your worst bolt. If it doesn't fit the gap, doesn't reach, or doesn't turn it, send it back for every dollar. No restocking fee, no argument.
KnuckleReach 15 - Offset Extension Wrench, 3/8"
Regular price
$79.00
Regular price
$79.00
Sale price
$109.00
Unit price
per
Awkward angles
Most ratchets want 45° before the teeth even engage. In a tight bay you don't have 45°. You have none.
Unreachable bolts
You can touch it with two fingers and still can't get a tool on it square. Busted knuckles are the toll.
Half a day gone
Half an hour on one bolt. An hour on one plug. A whole afternoon on a job the book calls forty minutes.
Spin here. Turn there.
A sealed roller chain runs between the two square drives inside a rigid body. Because the body doesn't flex, none of your pull is lost — it all lands on the fastener, square.
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STEP 1:
Attach socket
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STEP 2:
Attach ratchet
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STEP 3:
Reach the bolt
You don't need it every day.
But the day you do, nothing else in the box will save you. That's the whole pitch and it's the one line that both reference stores and real owners independently landed on.
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DIY & HOME REPAIR
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CAR & TRUCK
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RV, BOAT & TRACTOR
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BIKE & ATV
Why KnuckleTools
Built Different.
72 Nm
Steel Chain Drive
No plastic. No flex. Full torque transfer — 1:1 — from any angle.
Zinc Plated
Zinc Plated Finish
Won’t chip. Won’t rust. Not another plastic toy.
15.4″ / 39 cm
Real Reach
Long enough to clear brackets, manifolds and firewalls. Only 0.7″ thin — fits where nothing else does.
72 Nm.
Rated for real automotive torque.
No slip. No skip. No excuses.
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Zero Swing Arc
No room to swing? Doesn’t matter.
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0.7″ Thin
Fits where your hand can’t.
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No Wobble Under Load
Chain drive locks solid the second you apply torque.
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Works With What You Own
¼″, ⅜″, ½″ drive. 3 adapters + a ¼″ hex socket included.
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Designed In The USA
A3 carbon steel, zinc plated. Built to last.
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2-Year Warranty
Against any defect. No questions. No hoops.
Trusted By 30,000+ Customers
Professional mechanics and DIY enthusiasts rely on Wildbear Tools for precision and reliability.
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I was skeptical when seeing the ad, but then also my friend told me that he has this tool and explained how useful he finds it. After that, I saw another ad and decided to purchase, and I have absolutely no regret. It's an amazing tool. I got full set LOL
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I'm not a professional, but I have 2 ATVs and 3 bikes, and I just like to do repairs on my own. I also have an old F150 that needs some maintenance, and I have learned a lot of lessons doing the repairs myself. Friend showed me this offset extension, and I can't imagine being without it for all these repairs. It's so much easier now.
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Been a home mechanic for 15 years and this extension is a game changer. I also purchased the max version, and I find both very useful. The VisiPro lamp is actually useful too. Worth every dollar.
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I am an old guy, RV owner, and I am still from the days when you were supposed to repair most of the things yourself. I am on the road 3-4 months per year, and I find this tool very useful when I need to do any repairs in the Bay Area, especially in the tight spots that I was struggling with for years with.
Straight answers
Frequently asked questions
Will BOLTHERO fit MY tight spot?
Will BOLTHERO fit MY tight spot?
At 0.7" thick and 15.2" long, KnuckleReach fits where standard ratchets, wobble extensions, and flex-head wrenches can't go.
What this means for you:
- If there's a straight path to the bolt, this reaches it
- Slides past brackets, manifolds, firewalls, and hoses
- Works on most engine bay, motorcycle, and household repair tight spots
Not sure if it'll work for your specific situation? 100-day return policy if it doesn't fit.
Will the socket fall off during use?
Will the socket fall off during use?
No. KnuckleReach uses a spring-loaded steel detent ball that locks the socket firmly in place.
Stays secure when:
- The tool is inverted
- Used overhead
- Under heavy torque
We engineered the detent specifically to prevent this, one of the most common complaints with cheaper alternatives.
Is it strong enough? Will it bend or break under load?
Is it strong enough? Will it bend or break under load?
Rated to 72 Nm (53 ft-lb), covering the vast majority of automotive, motorcycle, and home repair work.
Built with:
- Zinc-plated A3 carbon steel body
- Internal steel roller chain (same principle that powers motorcycles and industrial machinery)
- Handles full torque without flex or wobble
Backed by our 2-year warranty against defects.
Can I use it to both tighten AND loosen bolts?
Can I use it to both tighten AND loosen bolts?
Yes. KnuckleReach chain drive transfers torque equally in both directions.
- Tighten the bolt going in, then loosen the same bolt coming out
- No tool swap mid-job
- 1:1 torque ratio in either direction
One tool for assembly and disassembly.
Does it work with my impact wrench and existing sockets?
Does it work with my impact wrench and existing sockets?
Yes. Works with any 1/4", 3/8", or 1/2" drive socket, with 3 adapters + a 1/4" hex socket included in the box.
Tool compatibility:
- Manual ratchets and breaker bars: no restrictions
- Cordless impact wrenches: setting 1 or 2 max (most brands deliver 20 to 40 Nm on setting 1)
- Pneumatic impacts: keep compressor pressure at 2 to 3 bar max
Compatible brands: Milwaukee, DeWalt, Ryobi, Makita, Bosch, and most major brands.
How fast does KnuckleReach pay for itself?
How fast does KnuckleReach pay for itself?
Usually on the first job.
Average shop quotes our customers come in with:
- $400 to $2,400 for jobs they end up doing themselves with BoltHero
At $69, the tool pays for itself almost immediately. Every job after that is pure savings.
How long does shipping take?
How long does shipping take?
Free worldwide shipping on every order.
Delivery times:
- US & Canada: 6 to 12 business days
- UK & Ireland: 5 to 8 days
- Australia & New Zealand: 6 to 10 days
- Europe: 6 to 10 days
You'll receive a tracking number as soon as your tool ships from our warehouse.
What if it doesn't work for me? Can I return it?
What if it doesn't work for me? Can I return it?
100 day guarantee.
- Try it on your worst bolt for up to 100 days
- If it doesn't earn its spot in your toolbox, ship it back for a full refund
- No restocking fees
- No email chains
- No questions asked
We refund every cent.