LESTER DUMAKUDE
Mr Chairperson, I've started with the clock one.  The second one is a limpet mine where metal plates are used to set it on.  The third one, it's a remote where waves between two mini-radios or walkie talkies are used to transmit the wave that you want to trigger the mechanism with.  Here they were going to act as a backup to one another in the sense that based on our experience, it happens that at times things don't go according to the plans.  Here it was to make sure that if whatever happened not all of them will be faced with the same circumstances.  That was the purpose of having three to back up one another.