The Larson SecurePRO L201/L201E delivers tested break-in protection with stainless steel mesh that withstands over 1,000 pounds of force — actual security, not just the appearance of it. These exterior-mounted storm windows transform vulnerable ground-floor windows into fortified barriers while cutting energy loss by up to 60% with the Low-E option.
For Montana contractors dealing with 90 mph wind events and temperature swings that can hit 100 degrees in a day, the SecurePRO offers measurable performance: 15,000 pounds of compression force holds the security mesh in place, powder-coated wire resists corrosion, and ENERGY STAR certification for Northern zones confirms the energy savings aren’t just marketing claims.
Security Specifications That Matter
The stainless steel wire mesh forms the heart of this system — 12 weaves per square inch of .028-inch diameter wire, powder-coated for weather resistance. This isn’t decorative screening. Testing shows the mesh surpasses 1,000 pounds of break-in force, and the frame secures it with 15,000 pounds of compression force.
| Security Specification | Value | Source |
|---|---|---|
| Break-in force rating | >1,000 lb | Tested |
| Mesh securing force | 15,000 lb | Manufacturer |
| Wire diameter | .028 inch | Manufacturer |
| Weave density | 12 per sq inch | Manufacturer |
| Wire coating | Powder coated | Manufacturer |
| Impact standards | Meets highest SMA level | Manufacturer |
The heavy-duty aluminum tubular frame with butt-joint corners handles wind loads up to 90 mph — critical for Montana’s chinook winds and severe weather events. An emergency release system in the lower sash ensures occupants can escape if needed, addressing the common concern about security products becoming fire hazards.
Installation Details for Contractors
These units mount on the exterior as over-window retrofits, with overlap mounting recommended for best protection. The security comes from the mounting system itself: four tamper-proof, one-way screws prevent removal from the outside. Once those screws go in, they’re not coming out without destroying them.
The L201 fits single-hung windows while the L201E accommodates double-hung windows, both including half-screens for bottom ventilation. Standard rough opening measures 24 x 39 inches with a finished size of 25 x 39.75 inches. White is the available color option.
The exterior mounting design means no interior trim work or finish carpentry. Contractors can complete installations without entering the home — ideal for occupied properties or security-conscious customers who prefer minimal interior access.
Energy Performance Beyond Security
The self-storing glass panel provides genuine insulation value, with Low-E coating reducing energy loss by up to 60%. ENERGY STAR certification for Northern and North-Central climate zones confirms these windows meet efficiency standards for Montana’s climate.
Double weatherstripping on both sash sides creates an airtight seal — critical when Montana winter temperatures hit -20°F while interiors stay at 70°F. That 90-degree differential drives serious infiltration through poorly sealed windows. The SecurePRO addresses both security and energy waste in one installation.
| Energy Specification | Value |
|---|---|
| Low-E energy reduction | Up to 60% |
| ENERGY STAR zones | Northern, North-Central |
| Glass type | Single-glazed, self-storing |
| Weatherstripping | Double on both sash sides |
Warranty Coverage
Larson backs the SecurePRO with a Limited Lifetime Frame Warranty, one-year finish warranty, one-year warranty on handle set, closer, and glass frame, plus a 5-year warranty on retractable screens if present. While discontinued after December 22, 2022, replacement parts and warranty service remain available.
Who Should Install SecurePRO Windows
Ground-floor vulnerability drives most SecurePRO installations. Contractors working on homes near wooded areas (where concealment aids break-ins), properties with valuable equipment visible through windows, or residences where owners travel frequently find these units solve real security concerns. The 90 mph wind rating also makes them suitable for homes exposed to severe weather — particularly properties on ridge lines or open terrain where wind loads exceed standard window ratings.
Skip these for upper-story windows where break-in risk is minimal. The security features add cost without benefit in those applications. Also avoid them on windows that serve as primary emergency exits unless the customer fully understands the emergency release operation.
The combination of legitimate security ratings (not just marketing claims), Northern climate energy certification, and exterior retrofit design that preserves interior finishes makes the SecurePRO L201/L201E worth considering for Montana’s specific challenges. At the price premium these command over standard storm windows, the measurable security and energy benefits need to justify the investment. For vulnerable ground-floor windows in quality homes, they often do.
Frequently Asked Questions
Q: What’s the actual break-in resistance of the Larson SecurePRO L201/L201E security mesh?
The Larson SecurePRO’s stainless steel wire mesh withstands over 1,000 pounds of break-in force in testing, with 15,000 pounds of compression force holding the mesh in the frame. The mesh uses .028-inch diameter wire with 12 weaves per square inch, meeting the highest level of SMA impact force standards.
Q: How much energy savings can I expect from the Larson SecurePRO with Low-E glass?
Low-E coating reduces energy loss by up to 60% according to manufacturer data. ENERGY STAR certification for Northern and North-Central climate zones confirms these windows meet efficiency standards for Montana’s climate. The self-storing glass panel combined with double weatherstripping on both sash sides creates an effective thermal barrier.
Q: Can the Larson SecurePRO L201/L201E handle Montana’s wind conditions?
Yes, the Larson SecurePRO is rated for wind speeds up to 90 mph, using a heavy-duty aluminum tubular frame with butt-joint corners. The exterior overlap mounting design and four tamper-proof, one-way screws ensure the unit stays secure during high-wind events.
Q: What’s the difference between the Larson L201 and L201E models?
The Larson SecurePRO L201 is designed for single-hung windows while the L201E fits double-hung windows. Both models include half-screens for bottom ventilation and share the same 24 x 39 inch rough opening size (25 x 39.75 inches finished size).
Q: How does the emergency escape system work on the Larson SecurePRO?
The Larson SecurePRO L201/L201E includes an emergency escape/release system built into the lower sash, allowing occupants to exit through the window despite the security features. The system maintains security from outside intrusion while ensuring the window can serve as an emergency exit from inside.
Q: Is the Larson SecurePRO L201/L201E still available for purchase?
The Larson SecurePRO L201/L201E was discontinued after December 22, 2022, but Larson continues to provide replacement parts and warranty service. The warranty includes Limited Lifetime coverage on the frame, one year on finish and components, and five years on retractable screens if present.
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