Instruction: Given a question and its related document, determine if the question is answerable by analyzing the information in the document. Output yes if the document addresses the question, or no otherwise.

Input:
Question: Whats the actual size of the bulb? Is it a standard 3.8in (width), & fits a 4 inch can? Or is this the size smaller to fit the 3in. can?
Document: My house is a no CFL household....and if you really do the math on those..a very bad investment as they almost never get anywhere near the expected lifespan...and I have had 3 out 4 CFL warranty claims rejected after several different types failed within months. So with that rant over,  I have been waiting for LED's to get better.I like the warmer like so nothing greater than 2700K and this light fits the bill.
With the dimmer slide way down, the incandescent bulbs are barely glowing but the LED won't go lower than about 1/3 brightness.Light disperson: Instead of even brightness across the face of the flood, the LED bulb has a brighter circular area about the size of a silver dollar in the center, surrounded by a noticeably darker donut ring from there to the edge. But this doesn't appear to significantly impact the evenness of light dispersal.
They are expensive for retrofit at 50 bucks each and I wish these were available when I built my house 2 years ago. The color is excellent but they are a lot brighter and more comparable to a 75-watt bulb. I use them with a dimmer at 50% or less). I've started to use the Cree's to replace my outdoor 4-inch cans since the Philips R20s are not designed for outdoor use.
People write that these are a great replacement for flood lights so I expected the bulb to be bigger. The bulbs in our kitchen are about twice the width of a regular bulb and that is what I think of for a flood light. These lights are about the same size as a regular bulb, but the light is directed down instead of all directions.
Because of these issues, I've continued to use energy saving Halogens in fixtures controlled by Insteon. I've now changed my 4" recessed ceiling fixtures over to the Philips LED R20 flood bulb, with great results because of the much improved dimming.The ramp down is smooth with a gradual decline (no steps) throughout the range down to 10%. At 9% it turns off and takes 3.0 seconds to go completely dark. I suspect a capacitor is discharging for this final ramp down.
I've been buying LED bulbs a few every 4 months or so to monitor the improvements to the lines. I own a construction company and we install hundreds of Par 20, 30 and 38 bulbs every year. We build fussy homes and don't install standard incandescent bulbs because the lens like quality of the halogen bulbs make light that is more even has a nicer CRI. I'm still looking to switch to LEDs one day.This is the first LED bulb I've purchased that I consider superior in quality to a halogen par20.
Gone are the fins and strange shapes of early LEDs that could make fixture-fitting a challenge. This fit the recessed can perfectly, with size and shape almost identical to the adjacent incandescent bulbs. When the bulbs are off, it's difficult to tell which is the LED.Light color. Again, difficult to distinguish from the soft, warm light of the adjacent incandescents. Much less sharp glare than a halogen.Brightness / dimming: Instantly on at full brightness. Slightly brighter than the 50W incandescents.
I bought 7 of these to replace 50w. R20's in kitchen small recessed fixtures They are exactly the same size, fit perfectly. Phillips makes quality products. I get the same warm white color, same or slightly better light output. I'm saving 300 watts every time they are switched on. The old R20's ran at 215F. These run at 80F.,only 10 degrees above ambient.. barely warm.They are dimmable with a special dimmer, according to the info on the package.
I replaced some R20 incandescent bulbs in the 4 inch cans in my kitchen with these. They are currently mixed and you cannot tell the difference between the incandescents and the new LEDs (I use Philips brand 45-watt R20 incandescents from Home Depot). My main gripe with the other LED replacements were the color (I preferred the warm 2700K color - most replacements were 3000k). They also had to be dimmable and compatible with Insteon dimmers.
The bulb has a nice color of light but is longer than a standard par 20. It is useless waste of money because it sticks out of the can light fixture. Do not buy.
Answer: no