4Sevens: Redefining the Flashlight

OTF: Out The Front Lumens

"Out-the-front" refers to the actual lumens measured out the front of your flashlight. Sometimes, this is referred to as "torch" lumens. OTF or "torch" lumens are not the same as "bulb lumens," "LED manufacturer ratings," or "emitter lumens." Many manufacturers will purposely fail to state how they obtain their "lumens" to inflate their numbers and to be more competitive on the shelf. We never do that. Our lumens are REAL lumens.

Some manufacturers state "up to XXX lumens" or will state possible outputs given perfect conditions between the LED and what you're shining it on. In reality, some lumens are "lost" as they travel from the LED out the front of the flashlight. The reflector and the lens both absorb some of the light, and this diminishes the total lumens that actually shine out.

So, how do our stated out-the-front lumens compare to typical "bulb lumens" stated by other manufacturers?

Typically, bulb lumens 'overstate' actual OTF lumens by 30-40%! This means our lights will outperform many others that claim 40%-60% higher lumens. For example, the 4Sevens Preon I is rated at 70 OTF lumens, but it will outshine some lights that claim "110 lumens." The Preon II is rated at 160 OTF lumens and will outshine some "240 lumens" lights!

In other words, to compare our OTF lumens with most other brands' stated "bulb lumens," just multiply our high-end ratings by 1.4 or 1.6.

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