On August 7, 2019, the Company’s Board of Directors approved a transition plan for the Company’s China manufacturing operations. As part of the plan, the Company is transitioning high-volume manufacturing from its Tianjin, China facility to contract manufacturers in China and elsewhere in order to reduce fixed costs in China, optimize the cost structure of the antenna product line, and create flexibility in antenna manufacturing due to the uncertainty of the lease of the current manufacturing premises, as described below. For the year ended December 31, 2020, the Company incurred restructuring expenses of $0.1 million for employee severance related to the separation of 12 employees and for the year ended December 31, 2019, the Company incurred restructuring expenses of $0.5 million for employee severance and related benefits related to the separation of 84 employees. Severance costs were paid from the Company’s cash in its China bank accounts.

On October 8, 2020, the lease of the premises on which the Company’s China manufacturing operations are conducted expired and the renewal is pending and uncertain. The Company has been notified that the Chinese Party Central Committee and the State Council are accelerating the layout optimization and transformation of the industrial park in which the Company’s leased premises is located and, accordingly, leases and lease extensions for all premises in the industrial park have been suspended and rent collection has been postponed. The Company has not received an indication of the likelihood of approval of its lease extension. However, should the lease ultimately be extended, rent will be due for the period of the lease suspension. As a result of the uncertainty regarding the Tianjin Lease (as defined in Note 11) renewal, the Company is refining its transition plan for the manufacturing activities conducted on the leased premises. As part of the refined transition plan, the Company will retain a group of employees in Tianjin, China, but will reduce additional headcount in Tianjin and incur additional restructuring charges.. The Company expects the transition to be substantially completed by the end of the 2021 fiscal year.

The following table summarizes the restructuring activity during the six months ended June 30, 2021 and the status of the reserves at June 30, 2021:

			Lease
	Severance		Termination			Total
Balance at December 31, 2020	$	0	$	15		$	15
Restructuring expense		60		0			60
Payments made		0		(15	)		(15	)
Balance at June 30, 2021	$	60	$	0		$	60

The restructuring liability is recorded in accrued liabilities on the condensed consolidated balance sheet at June 30, 2021 and December 31, 2020.

The Company allows its major distributors and certain other customers to return unused product under specified terms and conditions. The Company accrues for product returns based on historical sales and return trends. The refund liability related to estimated sales returns was $0.2 million and $0.1 million at June 30, 2021 and December 31, 2020, respectively, and is included within accrued liabilities on the accompanying condensed consolidated balance sheets.

The Company offers repair and replacement warranties of up to five years for certain antenna products and test & measurement products. The Company’s warranty reserve is based on historical sales and costs of repair and replacement trends. The warranty reserve was $0.3 million at June 30, 2021 and $0.3 million at June 30, 2020, respectively, and is included in accrued liabilities in the accompanying condensed consolidated balance sheets.

The following table summarizes the warranty activity during the six months ended June 30, 2021 and 2020:

	Six Months Ended June 30,
	2021			2020
Beginning balance	$	285		$	444
Provisions for warranties		57			3
Consumption of reserves		(58	)		(179	)
Ending balance	$	284		$	268