Please note that we are experiencing a surge in demand for hydrophones. We have very limited stock and are now building nearly everything to order. Please expect a lead time of approximately one week for production of your order. We pride ourselves on quick delivery and ask for your patience during this busy time. You might also consider checking stock with our resellers, which you can find under the support tab. If you have a deadline for delivery, we recommend leaving that note on your order form. Thank you!