Button optional:

LED color: White LED, Blue LED,Red LED, other color LED;
Braille: without braille
Button Surface: Flat surface
Connection: samll terminal connection 
Voltage: 24VDC, 12VDC, 6VDC
Normal Open, Normal Closed,
Number & Figure in button surface: no.:1.2.3....64, figure:
Door Open, Door Close, Arrow Up, Arrow Down, Alarm Bell,
telephone, G, B, P, B1, B2, etc.;

Feature:

Button surface material: Outer frame material are ABS/stainless steel plating, button surface cover material is stainless steel
The thickness of installation plate: 2-3mm, Installed by plastic clipping.
Fire-proof components, in accordance with European standard EN-81
Life: > 5 million of operation life.

Figure dimension (mm):