The Lock Measuring Tape is an innovative makeover of the common measuring tape: high on convenience, comfort and quality. But before you invest in one, here is a list of features that you should look for. The tape is a flexible form of ruler. It is usually a ribbon of cloth, plastic, fiber glass, or metal strip with linear-measurement markings. A tape measure, also called measuring tape, is a type of flexible ruler. Simply put, auto-lock tape measures are an innovative makeover of the common measuring tape: high on convenience, comfort and quality. The Lock Measuring Tape is very effective.