RAM MOUNTS Twist-Lock Suction Cup Mount with Universal X-Grip Cell Phone Holder Mobile Adapters This is a 12-step rotary

This is a 12-step rotary encoder with a nice ‘clicking’ feel

You can use these for tap or knock sensors pretty easily by reading the voltage on the output

Using test methods: D 3652

Built-in signal-strength indicator

It also can be set to one of sixteen available channels to limit interference and supports flash sync speeds of up to 1/200 second

RAM MOUNTS Twist-Lock Suction Cup Mount with Universal X-Grip Cell Phone Holder Mobile Adapters This is a 12-step rotaryFits Devices 1. 88 to 3. 25" Wide 3" Arm 3. 25" Twist Lock Suction Cup Base Attaches to Smooth, Non Porous Surfaces 1" Diameter Rubber Ball and Socket Rustproof Composite and Stainless Steel The RAM Twist Lock Suction Cup Mount from RAM Mounts consists of a 3. 25 twist lock suction cup base, a 3" double socket arm, and a universal spring loaded X Grip holder for cell phones. The suction cup twist lock base has a strong hold on glass and non porous