What information is not found on the protective collar of a DOT cylinder?

The protective collar of a DOT cylinder primarily contains crucial information related to the safety and regulatory compliance of the propane cylinder. This typically includes details such as the inspector's initials, which let users know who certified the cylinder's safety and serviceability, as well as the manufacturer of the cylinder, which helps trace the product back to its origin for quality control and accountability.

While the dip tube length can sometimes be indicated to assist in proper installation and operation, the propane capacity, measured in pounds, is not typically included on the protective collar. This detail is often found elsewhere on the cylinder's label, where it pertains to the maximum amount of propane the cylinder can safely contain, provided for users to understand the operational limits.

The absence of the propane capacity from the protective collar is essential for safety, as it helps to keep the collar uncluttered, ensuring that critical information is readily visible and understandable, while other specifications can be provided on different parts of the cylinder. Thus, while capacity details are important, they are not typically displayed on the collar itself, making this option correct.