Two ways to steady the top of a ladder, built for different jobs.
Lock Jaw Ladder Grip and the Werner AC78 do different jobs. The Werner AC78 is a standoff: it holds the top of the ladder away from a wall. Lock Jaw is a gutter clamp: it clamps the top of the ladder to a gutter so it can’t slide sideways.
So the choice comes down to where the top of your ladder rests: against a wall, or on a gutter.
What Each Device Does
Werner AC78: holds the ladder off the wall
The Werner AC78 QuickClick stabilizer is an aluminum-steel accessory that attaches near the top of an extension ladder. Its arms span about 44 inches and rest against the wall with mar-resistant rubber end caps, holding the ladder about 10 inches away from the surface.
- Attaches: with a spring-loaded locking latch, without tools.
- What it’s for: giving you working space in front of a wall, and a wider contact area at the top.
- What it doesn’t do: clamp the ladder to anything. It rests against the surface.
Lock Jaw Ladder Grip: clamps the top to the gutter
Lock Jaw fits over the gutter lip and the ladder rail, and locks the two together.
- Attaches: it can be applied with one hand and locks on in seconds.
- Fits: it accommodates ladder rails up to approximately 2 inches (50 mm) wide, and works on most gutters with a lip.
- What it’s for: stopping the top sliding sideways, especially as you step on and off at a roof edge.
Fitting Lock Jaw over the gutter lip and ladder rail, one-handed
Source: Lock Jaw FAQs (product information, checked September 2026)
Side-by-Side Comparison
| Lock Jaw Ladder Grip | Werner AC78 | |
|---|---|---|
| Type | Gutter clamp | Standoff stabilizer |
| Main job | Clamps the ladder top to the gutter | Holds the ladder top away from the wall |
| Where the top rests | On the gutter | Against the wall |
| Attaches | At the top, one-handed; locks on in seconds | Near the top, spring-loaded latch, no tools |
| Weight | About 1.9 lb (864 g) | About 6.4 lb |
| Standoff from the surface | None; the ladder sits at the gutter | About 10 inches |
| Width | Compact; fits one rail | About 44 inches span |
| Ladder fit | Rails up to approximately 2 inches (50 mm) wide | Extension ladders up to 40 ft; not Type III aluminum, Type II fiberglass extension or MT series ladders |
| Gutter needed? | Yes, most gutters with a lip | No |
| Not suitable for | Vinyl gutters, fixed metal leaf guards, loose or damaged gutters | Use with ladder jacks using planks or stages |
| Price (at time of writing) | $129 | About $89 at US retailers |
Werner AC78 specifications from Werner’s product page; price from US retailers. Lock Jaw details from Lock Jaw’s FAQs and product page. All checked September 2026.
When a Standoff Suits
A standoff like the Werner AC78 makes sense when:
- The ladder rests against a wall, not a gutter.
- You need space in front of the wall to work on siding, windows, trim or paint.
- There’s no gutter, or the gutter can’t take a clamp, such as vinyl gutters or fixed metal guards.
- You want the ladder to have a wider footprint at the top.
Keep in mind that a standoff doesn’t clamp the ladder to anything. Check your ladder is on Werner’s compatible list before buying.
When a Gutter Clamp Suits
A gutter clamp like Lock Jaw makes sense when:
- The ladder rests on a gutter and you’re stepping onto the roof.
- You want the top held in place, not just resting against a surface.
- You work alone and want to secure the top quickly. Lock Jaw can be applied with one hand and locks on in seconds.
- The gutter is sound and has a lip. Lock Jaw works on most gutters with a lip.
Keep in mind that a gutter clamp relies on the gutter. Only use it on a gutter that’s stable enough to rest a ladder on.
Lock Jaw on a K-style gutter
Using Both
The Werner AC78 and Lock Jaw aren’t designed to work together in one setup. One holds the ladder off the wall; the other clamps it to the gutter. Some people keep both and pick based on the job:
- Roof access from a sound gutter: Lock Jaw
- Painting, windows or siding against a wall: Werner AC78
- Vinyl gutters or no gutter: Werner AC78
- Working alone, stepping onto the roof: Lock Jaw
Whichever you use, OSHA’s ladder standard still applies. Two key rules:
“Ladders shall be used only on stable and level surfaces unless secured to prevent accidental displacement.” — OSHA 1926.1053(b)(6)
“When portable ladders are used for access to an upper landing surface, the ladder side rails shall extend at least 3 feet (.9 m) above the upper landing surface to which the ladder is used to gain access…” — OSHA 1926.1053(b)(1)
Source: OSHA ladder standard 1926.1053 (last amended April 2014, checked September 2026)
FAQs
What’s the difference between the Werner AC78 and Lock Jaw?
The Werner AC78 is a standoff that holds the ladder away from a wall. Lock Jaw is a gutter clamp that clamps the top of the ladder to a gutter.
Does the Werner AC78 lock the ladder in place?
No. It rests against the wall with rubber end caps and widens the ladder’s contact at the top, but it doesn’t clamp to the building.
Will Lock Jaw fit my ladder?
Lock Jaw accommodates ladder rails up to approximately 2 inches (50 mm) wide. It fits some, but not all, telescopic ladders.
Will Lock Jaw fit my gutter?
Lock Jaw works on most gutters with a lip. It isn’t suitable for vinyl gutters or fixed metal leaf guards.
Will the Werner AC78 fit my ladder?
Werner says it’s for ladders up to 40 feet, and not for Type III aluminum, Type II fiberglass extension or MT series ladders. Confirm with Werner for your ladder model.
Can I use both at the same time?
They aren’t designed to work together in one setup. Choose based on whether the top of the ladder rests against a wall or on a gutter.
Related Reading
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