The number of samples to procure for ENERGY STAR verification testing of decorative light strings should be the same as the number of units required for certification testing. Per the ENERGY STAR Decorative Light Strings Specification, three (3) samples should be used for each of the three (3) tests—Electrical, Output and Reliability, and Weathering—and all samples must be different. Therefore, nine (9) total samples are required for verification testing. For an indoor model which does not require the weathering test, six (6) total samples are required.