http://www.robotcombat.com/marketplace_switches.htmlhttp://www.robotcombat.com/marketplace_switches.html

These seem to be the main types available to the US. Personally i have seen 2 of them being used (the team whyachi and the Hella Master Power Switch) The both seem very safe to me and were allowed in robot wars (well the hella master power switch anyway) as centurian used to use one.

Just my opinion

Regards
Ian