Intensely engineered, high-voltage reed switches. How many volts can we help you handle?

Work faster, harder, and farther than you ever imagined.

Stable contact resistance from 30 mW to 100 watts.

HSI presents the world's smallest Form B reed switch.

Off the shelf or custom engineered...yeah, we've got a switch for that.

We engineer custom sensors for the world's most critical missions. Let us engineer yours.

Custom Engineering

Your project is full of possibility. But to make it work, you need a custom-designed sensor at the leading edge of its capability. You need HSI Sensing.

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HSI's trusted line of fully customizable, smart magnetic sensors are tamper-proof by design, and the only choice when access point security failure is not an option.

HSI Sensing

HSI Sensing is the innovative leader in the engineering, design, and precision manufacturing of custom reed switch and sensor technology. The industry experts at solving problems for customers in challenging design applications, we also precision manufacture those solutions for consistent, unmatched quality.

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Spot On Earns UL 1203 Certification

Spot On Earns UL 1203 Certification
All HSI Spot On models now come UL 1203 certified -- at no extra charge to the customer. Read More

HSI Expands Its Reach Beyond Oklahoma

HSI Expands Its Reach Beyond Oklahoma
HSI has opened a new development lab in Madison, Wisconsin that will focus on manufacturing technology, processes, and efficiencies. Read More