A ratchet suspension is a key feature found in many modern helmets, including those used in construction, industrial work, and other hazardous environments. The ratchet suspension system consists of an adjustable mechanism that allows for precise fitting and secure placement of the helmet on the wearer's head. It typically includes a strap or webbing that encircles the head, along with a ratchet mechanism that can be tightened or loosened to achieve the desired fit. This system offers several advantages over traditional suspension systems, such as pin-lock or snap-lock systems. The ratchet suspension provides a more customizable fit, accommodating a range of head sizes and shapes, and allowing for easy adjustments while the helmet is being worn. It enhances comfort by evenly distributing the weight of the helmet and reducing pressure points. 

The ratchet suspension ensures that the helmet remains securely in place during movement and prevents it from dislodging or falling off during work activities. Overall, the ratchet suspension system is a valuable feature that improves both comfort and safety for individuals wearing helmets in various industries and job roles.