Alpha 1.0 is thinner.
The Alpha 1.0 laser tilt mount has the calibration sensor near the bottom of the tilt rack. The Alpha 2.0 mount has the sensor near the middle of the frame, and is wider. If you have an Alpha 2.0 mount, press 'Cancel' and select 'Laser Tilt Alpha 2.0' from the menu.
Only Alpha 1.0 laser tilt assemblies have guards above the E-chain. Not all Alpha 1.0 devices have guards, so do not assume it is an Alpha 2.0 laser tilt if it does not.
Do not proceed if you are not sure.
Press 'Continue' to proceed.