Note 7 — Intangible assets, net

Intangible assets, net consisted of the following (in thousands):

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Amortization expense was $838,000 and $622,000 for the years ended December 31, 2019 and 2018, respectively. The estimated aggregate amortization expense in respect of these assets for each of the five years ended 2024 is $887,000, $668,000, $535,000, $102,000 and $-, respectively.