What it is on the BOM
The ABB 1SBL164001R1501 is an electrical contactor catalogued under Contactors and Starters within the broader Circuit Breakers, Fuses & Protection tree, and it shows up in panels wherever a small-frame contactor is specified into a motor or heating circuit.
Where this class sits in a panel
Contactors in this class are the workhorse switching element between a control output (PLC relay, pushbutton, thermostat) and the downstream load — motor starters, heating banks, lighting contactors, HVAC compressors — so the BOM line is usually driven by the load current and coil voltage rather than the contactor brand name on its own.