The "MR" in MR16 stands for Multifaceted Reflector. These facets on the inside surface provide optical control by gathering the light from the filament to create a concentrated beam of light. These flood lights are well suited to a variety of applications that require directional lighting of low to medium intensity, such as track lighting, recessed ceiling lights, desk lamps, pendant fixtures, landscape lighting, retail display lighting.
Lumens
With new light bulbs, shopping by lumens is more important than shopping by watts when choosing which energy-efficient bulb to purchase. While wattage measures the amount of energy required to light products, lumens measure the amount of light produced. This means that the more lumens the product has, the brighter the light source is. Instead of buying products based on how much energy they consume (watts), consumers should consider how much light they give us (lumens).
Wattage
Wattage is the measure of the bulb's energy consumption - not how much light it puts out. Energy-efficient bulbs use fewer watts to give off the same amount of brightness (lumens). Because of this, LEDs (which have typically low wattages when compared with lumens) not only help reduce energy usage but also lower electric bills.
Color Temperature
Color temperature refers to the color appearance of the light that comes from a light source. It's an important performance characteristic to asses when evaluating bulbs because the color temperature creates the mood of the space you are lighting and can thus influence buying behavior or work performance. The apparent color of a light source is measured in Kelvin. The higher the Kelvin temperature, the whiter the light.
Dimmable
Dimming LED bulbs gives you the same kind of flexibility and control you can expect from your incandescent bulbs. With so many improvements to this technology, it has become easier to find an appropriate energy-efficient replacement to work with your dimming system. You will save more energy and find a large reduction in your electrical bill while still getting the amount of light that you need with dimmable LEDs. Customers also use these dimmers for track lighting--where desirable ambient light levels are needed but where a dimmed light setting is also desirable.
Beam Spread
MR16 lamps contain engineered surfaces that control the beam of light to a precise angle. There are seven different classifications of these angles. Very Narrow Spot is at 7 degrees or less and casts an intense, focused beam. Narrow Spot is at 8 to 15 degrees and casts a slightly less focused beam. Spot is at 16 to 22 degrees and casts a medium-sized beam. Narrow Flood is at 23 to 32 degrees. Flood is at 36 to 45 degrees and casts a wide beam. Wide Flood is at 46 to 59 degrees and casts a dispersed beam to cover a large area. Very Wide Flood is over 60 degrees and casts an extremely wide beam.