This Specification provides the requirements for lock mandrels and landing nipples within the production/injection conduit for the installation of flow control or other equipment used in the petroleum and natural gas industries. It includes the interface connections to the flow control or other equipment, but does not cover the connections to the well conduit.

This edition of API Specification 14L is an identical adoption of ISO 16070, Petroleum and natural gas industries-Downhole equipment-Lock mandrels and landing nipples. This specification contains the API Monogram Annex as part of the U.S. national adoption.