These Aluminum metal buttons are rugged , waterproof and look real good . Simply drill a 16mm hole into any material up to 1/2" thick and you can fit these in place, there's even a rubber gasket to keep any water out of the enclosure. On the front of the button is a flat metal actuator, surrounded by a Blue plastic LED ring. On the back there are 3 contacts for the button (common, normally-open and normally-closed) and 2 for the Blue LED ring (+ and -). Connect 3 to 6V to the LED to have it light up nicely, there's a built in resistor! If you want to use this with a higher voltage, say 12V or 24V, simply add a 470 ohm resistor in series with the LED connection to keep the LED current at around 20mA.
This button is a momentary push button, when you press it the 'normally-open' contact shorts to the common contact. When you release it, the contacts open up again.
The switch and LED are separated, so you could wire it to turn on when pressed or vice versa or whatever you wish! Check the tech details for information!

Technical Details:

Protection Level: IP67
Max. Current: 3a
Max. Voltage: 250v
Material: Aluminum (BLACK ANODIZED)  
Shape:      HIGH FLAT round    (The actuator stays high out of the switch body in the non-pressed state)     
Diameter: 16mm
Voltage: 3a 250v
Function: on-off (momentary type)
Type:Anti-vandal type push button switch

Suitable for black front panels of height 1U