Our revenue is generated primarily from the sale of products. Product revenue primarily consists of sales of Celution devices and consumables for commercial and research purposes.

The Company’s contracts with customers only include one performance obligation (i.e., sale of the Company’s products). Typically, if there are multiple items included on a single order, they are delivered at the same time. Revenue is recognized at a point in time when delivery is completed and control of the promised goods is transferred to the customers. Revenue is measured as the amount of consideration the Company expects to be entitled to in exchange for those goods. The Company’s contracts do not involve financing elements as payment terms with customers are less than one year. The sale arrangements do not include any variable consideration. Advance payments from customers are recorded as deferred revenue.

Shipping and handling activities that occur after the customer obtains control of the goods are considered part of the Company’s obligation to transfer the products and therefore are recorded as direct selling expenses, as incurred.

	Three months ended
	March 31, 2019		March 31, 2018
Consumable	$	663	$	559
Device		-		94
Other products		40		78
	$	703	$	731

Product revenues, classified by geographic location, are as follows (in thousands):

	Three months ended
	March 31, 2019					March 31, 2018
	Product Revenues		% of Total			Product Revenues		% of Total
Americas	$	64		9	%	$	45		6	%
Japan		419		60	%		578		79	%
EMEA		150		21	%		90		12	%
Asia Pacific		70		10	%		18		3	%
Total product revenues	$	703		100	%	$	731		100	%

Two direct customers accounted for 57% of our revenue recognized for the three months ended March 31, 2019. Two direct customers accounted for 61% of total outstanding accounts receivable (excluding receivables from BARDA) as of March 31, 2019.

Four direct customers comprised 66% of our revenue recognized for the three months ended March 31, 2018. Three direct customers, two distributors and one licensee accounted for 75% of total outstanding accounts receivable as of March 31, 2018.

We earn revenue for performing tasks under research and development agreements with governmental agencies like BARDA which is outside of the scope of the new revenue recognition guidance. Revenues derived from reimbursement of direct out-of-pocket expenses for research costs associated with government contracts are recorded as government contracts and other within development revenues. Government contract revenue is recorded at the gross amount of the reimbursement. The costs associated with these reimbursements are reflected as a component of research and development expense in our statements of operations. We recognized $0.7 million in development revenue for the three months ended March 31, 2019, as compared to $0.9 million for the three months ended March 31, 2018.