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Preseason orders will begin to ship April 1st
Preseason orders will begin to ship April 1st

Custom Portable AC Window Insert for Single & Double Hung Windows

Custom Portable AC Window Insert for Single & Double Hung Windows

Hung windows do not utilize the same window screen replacement method as hinged windows. See the video under the main product image to see how it works.

Vent your portable AC through single and double hung windows without blocking your view or leaving gaps that leak hot air. This custom portable AC hung window vent kit is precision-cut from durable ¼" acrylic and sized to your exact window opening, creating a proper seal that actually keeps hot air outside.

Each insert eliminates the portable AC hose window gap that kills cooling efficiency. The quick-attach snap-fit collar locks securely into the panel, creating a sealed exhaust path so your portable AC vents outside instead of recirculating warm air back into the room.

Our hung window AC vent kit is designed for both single and double hung windows and installs using a non-permanent mounting system that sets up in minutes, no drilling required.

Standard inserts are available in 12" heights, with taller custom sizes available when needed.

Build Your Custom Insert
How to Use

A durable solution for venting through vertical sliding windows. This portable AC window insert for hung windows creates a proper seal for portable air conditioners, eliminating gaps that let hot air leak back inside and reducing cooling efficiency.

Product Details
  • Custom cut to your exact window measurements for a perfect fit.
  • Precision CNC machined from durable ¼" clear acrylic that won't warp or crack.
  • Quick-attach snap-fit collar creates a secure, airtight seal around your exhaust hose.

Finally, a Portable AC Vent That Actually Fits Hung Windows

Generic portable AC window kits rarely seal properly in single- or double-hung windows, leaving gaps that let hot air leak back inside.

 This custom portable AC window insert for hung windows is CNC-cut to your exact opening, creating a sealed exhaust path so your AC can cool the room properly.

  • Custom CNC-cut ¼″ acrylic window vent panel sized to your exact opening

  • Quick-attach snap-fit collar for secure, airtight hose connection

  • Non-permanent portable AC hung window installation in 5–10 minutes

  • Eliminates portable AC vent leaking hot air back into your space
Build Your Hung Window Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

Stop Fighting Generic Kits. Start Cooling Properly.

A precision-engineered venting solution that seals your hung window opening, allowing your portable AC to exhaust hot air outside while maintaining a tight fit for better cooling performance.
Stops Hot Air Leaks

Stops Hot Air Leaks

Generic accordion kits gap and buckle in hung windows. This creates an airtight seal so your AC cools the room, not the outdoors.

Built for Your Exact Window

Built for Your Exact Window

Measured and CNC-cut to your specifications for single or double hung windows. No makeshift solutions or stuffing gaps.

Install Without Tools

Install Without Tools

Slides into place and locks secure in under 10 minutes. Remove it anytime without damage.

See-Through Design

See-Through Design

¼" clear acrylic maintains your view and natural light while venting efficiently.

Hose Stays Put

Hose Stays Put

Snap-fit collar holds your exhaust hose firmly in place. No duct tape required.

Works on Any Hung Window

Works on Any Hung Window

Fits both single hung and double hung windows, custom-sized to your exact opening.

Build Your Hung Window Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

Install in Minutes. Remove Anytime. Zero Damage.

Measure your window opening, submit your dimensions, and we'll CNC-cut your insert to exact specifications. Installs in 5–10 minutes without drilling or permanent modifications. When summer ends, remove it and your window looks untouched.
Build Your Hung Window Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

A Portable AC Vent Designed for Hung Windows

Generic vent kits try to fit many window types, which usually means gaps and hot air leaking back inside. This custom portable AC window insert is cut for single and double-hung windows, creating a tight exhaust opening so hot air vents outside while your window stays functional.
Build Your Hung Window Insert
Trusted by thousands of homeowners who needed a real hung window vent solution.

Perfect Fit Guarantee

If your custom portable AC window insert for hung windows doesn't fit perfectly, we'll remake it – free of charge.

Even if the measuring mistake was yours.

Just email us what needs adjusting: "Make the width ½ inch shorter." "Tighten the height." Whatever it takes. We'll cut a new one and ship it the next business day. No hassle. No shipping fees. No leaving you stuck with a panel that doesn't seal.

Step-by-step measuring videos walk you through it
Snap-fit collar works with any portable AC hose size
Every measurement reviewed by our team before cutting
Wrong fit? We remake it free. No questions asked.
Build Your Hung Window Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

Let Your Portable AC Unit Finally Cool the Entire Room Properly

You notice it when the temperature climbs. The AC is running, but the room still feels warm because the window vent isn't sealing properly.

Most portable AC kits are designed for generic window openings and rarely fit single or double-hung windows correctly. Gaps around the panel let heat leak back into the room, forcing the system to run longer and work harder.

A custom portable AC window insert for hung windows solves that problem by sealing the opening and directing hot air outside where it belongs.

When the vent fits the window, the cooling system finally works the way it was meant to.

Better airflow. More consistent cooling. Less wasted energy.

Build Your Hung Window Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

Frequently Asked Questions

We'll remake it for free. Even if the measuring mistake was yours, just email us and we'll cut a new panel and ship it next business day, no charge.

Yes. Each portable AC hung window vent kit is custom-cut to your exact measurements, so it fits both single hung and double hung windows of any size.

Yes. The snap-fit collar is designed to work with standard portable AC exhaust hoses. If your hose diameter is non-standard, let us know during ordering and we'll adjust the vent opening.

No tools required. The insert slides into your window opening and locks in place in 5–10 minutes. It's completely non-permanent, remove it anytime and your window returns to normal.

Orders ship within 5–7 business days after we receive your measurements. Standard shipping is included. Expedited options are available at checkout if you need it sooner.

Hung Windows Done Right

Generic portable AC kits don't seal hung windows. This custom insert does.
★★★★★ 4.9/5 | 1,904
Martinson Manufacturing
Precision window inserts for hung windows.
Call Today 262-340-1418
Build Your Hung Insert 
Trusted by thousands of homeowners who needed a real hung window vent solution.

Martinson Manufacturing designs and produces precision window inserts for portable air conditioners. Built for non-standard windows, each insert is made to exact dimensions and engineered to fit cleanly, install easily, and perform reliably in real homes.

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Our Promise

Every insert we build is
designed to fit your window exactly, install cleanly, and work the way it should. If it doesn’t fit right, we’ll remake it. No workarounds, no damage, no guesswork, just a solution that performs reliably in your home. Every time.

Contact

Martinson Manufacturing
705 Schoenhaar Dr #101West Bend, WI 53090
262-340-1418
info@martinsonmanufacturing.com
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