The difference between a T2 and a T3 is the size (more precisely the width) of the tubing. T2 is 2/8 of an inch, T3 is 3/8 of an inch, and so on and so forth. The larger (thicker) tubes used in offices are usually T5 (5/8 of an inch), T8 (1 inch) or T12 (1.5 inches). The rule of thumb is the thinner the tube the more efficient the lamp, although other factors can affect the efficiency. For CFLs, the T2's allow manufacturers to make smaller bulbs often marketed as "micro minis".
energy efficient products
ENERGY STAR products are independently certified to save energy without sacrificing features or functionality. Saving energy helps prevent climate change. Look for the ENERGY STAR label to save money on your energy bills and help protect our environment.
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energy savings at home
Improving your home's energy efficiency with ENERGY STAR can help to lower high energy bills, improve comfort and reduce greenhouse gas emissions. Learn about the many ways to save in your home and track your progress with "My ENERGY STAR" - your new dashboard to savings.
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energy efficient new homes
A new home that has earned the ENERGY STAR label has undergone a process of inspections, testing, and verification to meet strict requirements set by the US EPA. ENERGY STAR certified homes use 15-30% less energy than typical new homes while delivering better comfort, quality, and durability.
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