Because of the industry we are in, availability of product is a constantly moving target. Our manufacturers are both incredibly reliable and efficient. Yet certain SKUs can still be hard to secure by their very nature - longer production times, hard-to-obtain materials, detailed construction processes, etc. Ordering items that are listed as "out of stock" on this site is still very much an option. Generally, as quickly as we run out of stock, we are able to replenish. There are always exceptions, but we do everything we can to speed up production and lead times for our customers. Simply contact us. The knowledge that our customers are in need of any out of stock product(s) will help us immediately kick manufacturer processes into high gear. We do all that we can for our customers. What happens if stock of an item is depleted after an order has been placed? Every effort is made to ensure that the items on our website are in our warehouse. But yes, athere will occasionally be times the website cannot catch up to our sales quick enough. If the item that you ordered is on backorder, you will be notified immediately by email and given the option to cancel your order. If you would like to confirm available stock before placing an order, please call us at 312-766-8808, or email sales@compressedgasvalve.com Further questions? Reach out! We are standing by.