Pollak 21-509 Precision Ball Switch – Normally Open (NO), Screw Terminals

Professional-Grade Accuracy for Heavy-Duty Systems

The Pollak 21-509 Precision Ball Switch is a high-reliability switching solution engineered for the demanding environments of the trucking, construction, and agricultural industries. This Normally Open (NO) switch is designed to provide immediate electrical activation upon contact, making it a critical component for vehicle safety and operational systems.

Simple and Secure Screw Terminal Design Featuring robust screw terminals, the 21-509 offers maximum flexibility for custom wiring and field repairs. This design eliminates the need for specialized mating connectors, allowing technicians to secure wire leads directly to the switch for a high-conductivity, vibration-resistant connection that stands up to the rigors of the road.

Built to Outlast the Competition Pollak switches are famous for their longevity, and the 21-509 is no exception. Constructed with a corrosion-resistant body and designed to operate in extreme temperatures ranging from -40°F to +250°F, it is ideal for mounting in engine compartments, transmissions, and chassis locations. With a mechanical life of 1,000,000 cycles, it is built for long-haul durability.

Key Specifications:

• Circuitry: Normally Open (NO)

• Termination: Two (2) Screw Terminals

• Thread Size: 9/16-18

• Hex Size: 7/8"

• Voltage Rating: 5.0 - 24.0 VDC

• Current Rating: 0.01 - 5.0 DC Amp

• Operating Temperature: -40°F to +250°F (-40°C to +121°C)

• Cycle Life: 500,000 Electrical / 1,000,000 Mechanical

• Installation: Includes O-ring seal for a leak-proof fit.