LEDs are broadly grouped by color, flux (lumens), and Forward Voltage when manufactured.
Color groups such as red, red-orange, cyan, cool white, warm white, etc., can encompass quite a wide color and temperature range.
For example, cyan LEDs can range from 490nm to 520nm, making the light output from cyan LEDs with a 520nm rating very ‘greenish.’ Similarly, red LEDs can range from 645nm to 620nm, making some red LEDs appear very ‘orangey.’

Flux and forward voltages can vary quite a bit for a single LED type. For example, the lumens output of the Rebel LXML-PWC1-0120 LED can range from 110 to 140 lumens, and the Forward Voltage from 2.55Vf to 3.99Vf.
For many applications, these ranges are far too broad to be useful, so as part of the manufacturing process every LED is tested to determine their exact color, flux, and Forward Voltage, with a ‘Bin’ number assigned to each parameter. The designer can request a specific Bin number if their application requires tighter tolerances.
Bin Number Structure
Bin numbers typically consist of a 3 or 4-letter/number code combination. For example, the Bin number for the LXML-PWC1-0120 will be 4 characters:
- 1st character: Flux Bin (e.g., J, K, L, M)
- 2nd and 3rd characters: Color Bin (e.g., W0, U0, V0)
- 4th character: Forward Voltage (Vf) Bin (e.g., D, E, F, G)
For instance, referring to the Product Binning and Labeling section of the LXML-PWC1-0120 datasheet, an LED with the following characteristics:
- Flux range: 130 to 140 lumens
- Color temperature: 6000K (cool white)
- Forward Voltage range: 2.79 to 3.03 Vf
would be assigned a Bin code of YW0C.
Purchasing Options
LEDs are sold in two ways:
- Reels – 1,000 or 2000 LEDs (depending on the color). All of the LEDs on the reel will be from the same Bin.
- Cut Tape – can be any LED quantity but may be selected from different reels and bins.
If you need to order LED modules with a tighter color, lumens output, or Forward Voltage specification, then you will need to order enough modules so they are built from full reels.
Lower quantities will be built using LEDs selected from our general inventory, which may be cut strips from different reels. So, a specific Bin number cannot be guaranteed.
You can learn more about how Luxeon Rebel LEDs are binned and labeled in the LED datasheets.
If you need LED modules built using a specific Bin number, contact us before ordering to determine availability.