Don-Jo AST-21342 Security Stri...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$40.62
Don-Jo AST-21342 Security Strike 18" x 1-3/4" Double Hole for 3-5/8" and 4" Centered Locksets, Silver Coated finish

Don-Jo AST-21342 Security Strike 18" x 1-3/4" Double Hole for 3-5/8" & 4" Centered Locksets

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Model: AST-21342-SL
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In Stock (leaves warehouse same day if ordered before 3pm ET)

$40.62
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Don-Jo AST-21342 Security Strike 18" x 1-3/4" Double Hole for 3-5/8" & 4" Centered Locksets

The Don-Jo AST-21342 is a commercial security strike measuring 18" in height and 1-3/4" in width, constructed from 13-gauge (.095) ferrous material. The double-hole design accommodates both 3-5/8" and 4" centered locksets, covering the two most common commercial lockset backset spacings in a single plate. Available in Brass Plated, Silver Coated, and White Coated finishes.

Key Features

  • 18" Height: Extended plate coverage for door frame reinforcement in commercial applications.
  • 1-3/4" Width: Fits standard commercial door frame preparations for a clean installation.
  • Double Hole Configuration: Accommodates both 3-5/8" and 4" centered locksets in a single strike.
  • 13-Gauge (.095) Ferrous Construction: Heavy-gauge material for structural integrity in high-security commercial door applications.
  • Three Finish Options: Brass Plated, Silver Coated, and White Coated to coordinate with door frame colors and hardware.
  • Shelf Pack of 10: Packaged for contractor and distributor efficiency on multi-door commercial projects.

Technical Specifications

  • Model: AST-21342
  • Height: 18"
  • Width: 1-3/4"
  • Gauge: 13-gauge (.095)
  • Material: Ferrous
  • Hole Configuration: Double hole - 3-5/8" and 4" centered locksets
  • Application: Commercial
  • Available Finishes: Brass Plated (BP), Silver Coated (SL), White Coated (WH)

Typical Applications

  • Commercial office buildings
  • Educational facilities
  • Healthcare institutions
  • Retail establishments
  • Industrial and warehouse facilities
  • Multi-tenant residential and apartment properties
  • Government and municipal buildings

Manufacturer Resources

DON-JO Strike Plates

Product Specs

Subcategory:
Door Strikes
Product Group:
Cylinders, Keys and Strikes
Product Subgroup:
Door Strikes and Strike Boxes
Product Type:
Reinforcing Strike
Commercial/Residential:
Commercial
Product Model:
AST-21342
Door Strike:
Security Strike
Product Category:
Parts and Accessories
Product Substrate:
Ferrous
Department:
Door Hardware

Don-Jo AST-21342-SL – Frequently Asked Questions

1) Will the Don-Jo AST-21342 security strike work with both 3-5/8" and 4" centered locksets?
That's exactly what the double hole design is for. The AST-21342 has two latch holes punched on the plate, one at 3-5/8 inch centers and one at 4 inch centers, so one part covers both of the common commercial lockset spacings you'll run into on a frame. Handy when you're reinforcing a building full of mixed openings and don't want to stock two SKUs.
2) How big is the Don-Jo AST-21342 strike plate, and will it cover the frame damage on a kicked-in door?
The plate measures 18 x 1-3/4 inches. That 18 inch run of coverage spreads the load well above and below the latch pocket, which is where a frame splits when a door gets kicked. It's a wrap of the existing strike area, not a replacement lock, so the latch and lockset stay as they are.
3) I need a strike for a pair of doors with no mullion, not a single opening. Is this the right part?
No. The AST-21342 is an 18 inch reinforcement plate for a single lockset location in a frame. For a double door application, look at the Detex 92 Strike Kit, which is a double door strike kit that comes with tamper resistant fasteners.
4) Do I have to change my lockset to install the Don-Jo AST-21342?
No lock change needed. The AST-21342 is frame side hardware only, a reinforcement strike plate that goes on the jamb over the existing strike area. Your existing latch keeps working through the plate's hole, provided the lockset centers are 3-5/8 or 4 inches, which are the two spacings the plate is punched for.
5) Is a Detex 92 strike kit a substitute for the Don-Jo AST-21342 security strike?
No, they solve different problems. The Don-Jo AST-21342 is an 18-inch by 1-3/4 inch ferrous security strike with a double hole for 3-5/8 inch and 4 inch centered locksets, used to reinforce the frame around an existing lockset latch. The Detex 92 Strike Kit is a double door strike kit supplied with tamper resistant fasteners and belongs to the Detex 90 Strike Series, which is the strike hardware that pairs with an exit device on a double door opening. If the opening has a cylindrical or mortise lockset on a single frame and you want added frame reinforcement, the AST-21342 is the part; if you are building out a double door exit device application, the Detex 92 kit is the strike hardware for that.
6) How thick is the metal on the Don-Jo AST-21342 security strike?
13 gauge, .095 inch, in ferrous material. That is heavy plate compared with the light strikes that ship in a lockset box, and it's the reason this one is specified for forced entry resistance rather than cosmetic patching.
7) How many Don-Jo AST-21342 strikes come in a pack?
They ship in shelf packs of 10. If you're doing a handful of doors you'll still be buying ten, so it suits a building-wide reinforcement pass better than a one-off repair.
8) What is the difference between a Don-Jo AST-21342 security strike and a Trimco 1260P pipe adapter strike?
They mount to different things. The Don-Jo AST-21342 is a commercial 18-inch ferrous strike plate, 1-3/4 inches wide, drilled with two latch holes so it serves locksets on either 3-5/8 inch or 4 inch centers. It is fastened to a conventional door frame or jamb. The Trimco 1260P is a pipe adapter strike, supplied as the strike only, and its purpose is to adapt a strike to pipe rather than to a flat jamb face. On a standard hollow metal or wood frame with a centered lockset, the AST-21342 is the applicable part; the 1260P is for the pipe mounting condition its adapter design is built around.
9) If a job needs tamper resistant fasteners at the strike, does the Don-Jo AST-21342 cover that?
The AST-21342 is specified by its plate: 13-gauge (.095) ferrous material, 18 inches tall by 1-3/4 inches wide, with the double hole pattern covering 3-5/8 inch and 4 inch lockset centers, in BP brass plated, SL silver coated, or WH white coated. Its security value comes from the heavy-gauge plate spreading force across the frame. Where the specification calls specifically for tamper resistant fasteners at the strike, the Detex 92 Strike Kit is supplied with tamper resistant fasteners, though it is a double door strike kit in the Detex 90 Strike Series rather than a frame reinforcement plate. Match the part to which requirement is actually driving the opening.
10) What finishes does the Don-Jo AST-21342 come in?
Three: BP brass plated, SL silver coated, and WH white coated. BP and SL are the usual picks against aluminum or bronze frames; WH matches painted white hollow metal, which is most multi-family and school frames. All three are the same 18 x 1-3/4 inch plate underneath.
11) Is the AST-21342 a residential strike or is it rated for commercial door frames?
Commercial. Don-Jo builds this one for office buildings, schools, healthcare, retail, warehouse, multi-tenant residential, and government work, which is why it's 13 gauge rather than the thin stamped plate you'd find on a house door.
12) Which model number do I give my supplier for the Don-Jo 18 inch double hole security strike?
Don-Jo AST-21342, listed by Don-Jo as model AST 21342. Add the finish code you want, BP, SL, or WH.
How fast can I get the Don-Jo AST-21342-SL delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Don-Jo AST-21342-SL come with a warranty?
Absolutely. The Don-Jo AST-21342-SL is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Don-Jo AST-21342-SL?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Don-Jo AST-21342-SL from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.

Product Reviews

  • 5
    Simple and Effective

    Posted by Isabella on Sep 7th 2023

    The Don-Jo AST-21342 from Zensupply is a no-frills strike plate that gets the job done. I like its sturdiness and easy installation. However, it lacks fancy finishes, so it's not the most stylish option. But if you're after security, it's a winner.

  • 5
    Elevate Your Security!

    Posted by Landon on Aug 24th 2023

    The Don-Jo AST-21342 is a sleek security plate that adds a touch of style. The durable construction gives me peace of mind, and the install was a snap. Just note, the price is a bit on the higher side. Class up your entrance with this plate!

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