4. OTHER INTANGIBLE ASSETS:

At December 31, 2011, the Company had the following intangible assets subject to amortization:

At December 31, 2010, the Company had the following intangible assets subject to amortization:

Patents and trademarks are amortized using the straight-line method over their useful lives of 17 years. Amortization expense on patents and trademarks was $122,798 and $118,394 for the years ended December 31, 2011 and 2010, respectively. Customer relationships are amortized using the straight-line method over their useful lives of 10 years. Amortization expense on customer relationships was $101,000 for both the years ended December 31, 2011 and 2010. Other intangible assets consist primarily of costs associated with product safety certifications (UL certifications), Energy Star certifications and non-compete agreements. Other intangible assets are amortized using the straight-line method over their useful lives, which range from 1-17 years and are periodically evaluated for recoverability in accordance with FASB ASC 350 "Intangibles – Goodwill and Other". Amortization expense on other intangible assets was $64,040 and $30,393 for the years ended December 31, 2011 and 2010, respectively. As of December 31, 2011, amortization expense on intangible assets for the next five years and thereafter is as follows, excluding $209,838 invested in patents which is not yet being amortized as the patent is not complete: