The Link-Belt 145 X4 Spin Ace is a hydraulic excavator in the Link-Belt X4 series, designed for general excavation, utility work, site preparation, and material handling. It features a compact tail swing configuration for improved maneuverability in confined job sites and is commonly used in urban construction, roadwork, and landscaping applications. The 145 X4 Spin Ace is part of Link-Belt's Spin Ace lineup, which emphasizes upperstructure rotation and working range for efficient operation in tight spaces. As an excavator, it is typically equipped with a boom, arm, bucket, and undercarriage suited to digging, trenching, and loading tasks.