Holman Aluminum GM Threshold Kit - Grey Model 40477G (REQUIRED)Holman Aluminum GM Threshold Kit Grey Model 40477G (REQUIRED) GM van Rear and Curbside Door Aluminum 5 Bar Tread Plate Threshold Kit. These aluminum tread plate thresholds protect your van from wear and tear from constant use. Features: Aluminum Thresholds replace the factory thresholds. Durable and attractive. Easily installed in any wheelbase GM van. Kit includes both curbside and rear door thresholds. Vehicle Fitment: 1996+ Chevy Express Extended