7.    Intangible Assets

The following provides a breakdown of identifiable intangible assets as of March 31, 2022 and December 31, 2021:

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In connection with the acquisitions of Sport Defense, the Company identified intangible assets of $55 thousand representing technology related and customer related intangibles. These assets are being amortized on a straight-line basis over their weighted average estimated useful life of 4.5 years and amortization expense amounted to $3 and $3 for the three months ended March 31, 2022 and 2021, respectively.

As of March 31, 2022, the estimated annual amortization expense for each of the next five fiscal years is as follows:

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