Based on this product's specifications, here are some alternatives and similar models
Height Adjustment Kit for TH-C1 by starmix, model 018447
Summary description:
Replacement height adjustment accessory for starmix TH-C1 vacuum/cleaning system, model 018447. Provides the factory-specified mechanism for setting or restoring cutting/working height on compatible TH-C1 units. Designed for maintenance and repair to ensure correct height control and reliable operation of the TH-C1 device.