The Wingmaster Stainless Steel Peterbilt Tool Box Filler Block is a practical and versatile accessory for your Peterbilt truck. Designed specifically for the bottom step, this stainless steel filler block is sold individually and fits most Peterbilt 389 makes and models. Its durable construction ensures long-lasting performance, while its easy installation makes it a convenient addition to your tool box. Enhance the functionality of your truck with this tool box filler block, providing a secure and organized storage solution.