QUOTE(aarondotcom @ Feb 14 2012, 05:44 PM)
sorry, can u explain more, how to nullified? I going to get a security door. which the contractor told me it is very secure, got 1 set for contractor and another set for home owner. But my doubt are, for contractor and for house owner not the same set? but accessing the same door lock?
Each door they have
1. 2 pcs contractor keys - This key will be the first keys you use, 1 for you, 1 for the contractor. All other keys should not be used. (master key works but will cause the contractor keys to be obsolete, general keys cant' be used)
2. 1 pcs master key - After renovation complete, use this keys once and the contractor keys will be nullified, obsolete, can not use. This will make the 5 general keys active, can use. This master key can still be used in case of emergencies if you lose all the other keys.
3. 5 pcs general keys - These keys are to be used as general keys after renovation.
It is designed this way so that after renovation, contractor can not use his contractor keys to unlock and access your house.