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Keystone 21W 48" 6500K Double-Sided T8 LED Sign Bulb, Ballast Bypass

SKU: KT-LED21T8-48P2S-865-D | Ordering Code: KT-LED21T8-48P2S-865-D  | UPC: 890949017395

$48.89each
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Options

Length (in)
28 33.8 39.8 45.8 57.8
Brightness (Lumens)
1600 2000 2250 2600 3250

Product Highlights

  • Estimated life of 45.7 years based on 3 hours use per day
  • No lead or mercury means easy and environmentally safe disposal
Description

Lighting Facts Per Bulb

Brightness 2600 lumens
Estimated Yearly Energy Cost $2.53
Based on 3 hrs/day, 11¢/kWh
Cost depends on rates and use
Life
Based on 3 hrs/day45.7 years
Light Appearance
WarmCool
6500 K
Energy Used21 watts

Keystone's 21 watt non-dimmable 48" 6500K double-sided ballast bypass T8 LED sign tube has LED modules on two sides and are designed for lighting marquees, box signs, backlit displays, roadway signs and many other types of outdoor and indoor displays. They are designed to replace T12HO and T8HO fluorescent lamps. Unlike standard LED lamps with 120° to 180° beam angles, the Keystone double-sided T8 lamp offers a virtual 360° distribution with individual optics that create bright and uniform illumination without any dark spots. The lamp comes in a 6500K color temperature to provide the best color quality and visual impact.

The ballast must be bypassed when present.

  • Fits a minimum length of 45.72" and a maximum of 45.91"
  • Ideal for both single sided and double sided signs
  • Installs using existing sockets in the sign
  • Optical lens over individual LEDs for optimal light spread within the sign
  • Listed on SAM manual for the state of CA
  • Effective 360° beam spread
  • Rotatable end caps
  • Double sided design provides even lighting in signs with no hot-spotting
  • UL Classified: LED sign retrofit, evaluated to UL 48 / UL 879A Standards
  • No external driver or power supply needed
  • Durable polycarbonate construction
  • 2600 total lumens; 1300 per side

 

Product Documents

Full Specs

Brand

Keystone

Model Number

KT-LED21T8-48P2S-865-D
Energy Used

Energy Used

A rating, expressed in watts, to indicate the rate at which a lamp consumes energy. Also known as wattage value.
 
21 Watts
Fluorescent Equivalent

Fluorescent Equivalent

The total wattage of fluorescent lamps in a fixture that this fixture replaces.
 
60
Volts

Volts

A measure of "electrical pressure" between two points. The voltage specification of an incandescent lamp is the electrical "pressure" required to drive it at its designed point. The "voltage" of a ballast (e.g. 120 V) refers to the line voltage coming from the power source and is connected to the ballast.
 
120-277
Base

Base

The end (or ends) of the lamp that fits into the socket.
 
R17d
Bulb Shape

Bulb Shape

The description of the general appearance of a lamp/bulb consists of a letter(s) followed by a number. The letter indicates the shape of the bulb and the number relates to the diameter of the bulb in eighths of an inch. For example, a common household bulb is the A-19. The bulb is "A" shape and the diameter would be nineteen 8ths of an inch, or 2 3/8".
 
T-8
Bulb Color

Bulb Color

The color of the light produced by a bulb
 
Daylight White
CRI

CRI

Color Rendering Index is an international system used to rate a lamp's ability to render object colors. The higher the CRI (based upon a 0-100 scale) the richer and more accurately colors generally appear. CRI differences among lamps are not usually visible to the eye unless the difference is more than 3-5 points.
 
80
Color Temperature (Kelvin)

Color Temperature (Kelvin)

An expression of the hue of the light emitted, measured in degrees Kelvin. Usually expressed by a four digit number followed by (k), such as 2700k. Higher temperatures indicate whiter, "cooler" colors, while lower temperatures indicate yellower, "warmer" colors. Some common Kelvin temperature benchmarks are 2700k (warm white), 3500k (neutral white), 4100k (cool white), 5000k (bright white), and 6500k (daylight).
 
6500
Brightness (Lumens)

Brightness (Lumens)

A rating of the initial light output of a bulb, rated after 100 hrs of operation. Lumens are a measure of how much light falls on one square foot of area, one foot away from the light source.
 
2600
Bulb Finish

Bulb Finish

The surface finish of a bulb, which may affect the quality of the light emitted.
 
Clear
Bulb Technology

Bulb Technology

The technology implemented by the bulb, e.g. incandescent, halogen, LED
 
LED
Average Rated Life (hr)

Average Rated Life (hr)

A measurement of the average length of time, between first use and the point when 50% of the lamps tested have stopped functioning, , using an operating cycle of 3 hours on, 20 minutes off.
 
50000
Operating Temperature (°F)

Operating Temperature (°F)

The ambient temperature in which the product can safely operate.
 
-4 to 131
Beam Angle (°)

Beam Angle (°)

The width of a light beam, expressed in degrees. The beam angle is often part of the ordering code for reflector lamps. For example, a 50PAR30/HIR/NFL25 is a 50-watt PAR30 narrow flood lamp with a beam angle of 25 degrees.
 
360
Bulb Power Type

Bulb Power Type

Defines how a lamp is powered, whether it needs a ballast or not, or can use either
 
Ballast Bypass
Length (in)

Length (in)

Also referred to as "Maximum Overall Length" (MOL). For light bulbs, it measures the length of a light bulb, from the top of the bulb to the bottom of the base or pins and is typically expressed in inches. For light fixtures and ballasts, it applies to the total horizontal length of the item.
 
45.8
Diameter (in)

Diameter (in)

Light bulbs: a measurement of a bulb's width taken at the widest point of the bulb. Fixtures: the measurement across the widest point of a circular fixture.
 
1.1

Warranty

5 year limited
Damp Location

Damp Location

Suitable for an exterior or interior location that is subject to condensation of moisture in, on or adjacent to electrical equipment
 
Yes
Rated for Fully Enclosed Fixtures

Rated for Fully Enclosed Fixtures

Not all LED bulbs are suitable for use in enclosed fixtures, due to the amount of heat they generate. Rated bulbs have been tested and approved as safe for enclosed fixtures.
 
Yes