Pollak 21-448 Precision Ball Switch – Normally Open (N.O.) with Heavy-Duty Screw Terminals

Reliable Triggering for Professional Truck and Industrial Systems

The Pollak 21-448 Precision Ball Switch is a high-performance, Single Pole Single Throw (SPST) Normally Open (N.O.) component. Engineered for accuracy and longevity, this switch remains in the "Off" position until the ball is depressed, at which point it completes the circuit. It is a critical component for backup light activation, neutral safety sensing, and specialized gear-position indicators in commercial vehicles.

Versatile Screw Terminal Design The 21-448 features heavy-duty screw terminals, offering maximum flexibility for field installations. Unlike specialized plug-in connectors, screw terminals allow you to connect wires using standard ring or spade terminals. This ensures a rock-solid, vibration-resistant connection that can be easily serviced or replaced without the need for proprietary wire harnesses.

Built for the Harsh Realities of the Road Designed to be mounted in transmissions, transfer cases, and chassis frames, the 21-448 is built to take a beating. The zinc-plated metal housing provides excellent resistance to corrosion, road salt, and moisture. Inside, the precision-ground ball and high-quality internal springs ensure smooth actuation and a long service life, even under constant mechanical stress.

Key Features:

• Normally Open (N.O.) Function: Momentary action completes the circuit only when the ball is pushed.

• Universal Screw Terminals: Provides a secure, bolted connection that is easy to service in the field.

• Corrosion-Resistant Housing: Zinc-plated steel construction protects against harsh environmental factors.

• Precision Engineering: Tight tolerances for accurate and repeatable switching performance.

• Standard 9/16" Thread: Fits most common heavy-duty transmission and machinery ports.

Common Applications:

• Commercial Truck Backup/Reverse Light Activation

• Neutral Safety Start Sensing

• Power Take-Off (PTO) Engagement Indicators

• Transmission Gear Position Monitoring

• Industrial Limit and Safety Interlocks