Garage Door rollers

Garage door rollers are small cylindrical wheels at the bottom of a garage door. They are designed to fit into the tracks on either side of the garage door and help the door move up and down smoothly. Rollers are made of different materials, such as steel, nylon, or plastic. Steel rollers are the most durable and heaviest, which can put more stress on the opener. Nylon and plastic rollers are less durable but quieter and lighter. There are two types of garage door rollers: 

Conventional rollers: These rollers have a stem that fits into a bracket on the garage door. These rollers are the most common type used in residential garage doors.

Stemless rollers: These have no stem and are mounted on the door using a built-in bearing. These rollers are less common but are becoming more popular because of their durability and ease of maintenance.

It's important to note that rollers with ball bearings are more durable than those without bearings. It's recommended to have the rollers inspected by a professional regularly and replace them if they are worn out, damaged, or make too much noise.