Description:
The 3561 roll ball switch will turn the digital input "on" when the roll ball is depressed, and will turn "off" when the ball is released.

Specifications:

• Sensor Type: Input (Switch)
• Sensor Output Switch Type: Normally Open
• Cable Length: 45.7 cm
• Cable Gauge: 22 AWG
• Travel: 6 mm
• Switching Current Max: 500 mA
• Switching Voltage Max (AC): 100 V AC
• Switching Voltage Max (DC): 100 V DC

Resources:
Product Datasheet