Electrical safety adaptor with replaceable head unit

An electrical safety adaptor for an electric socket, comprising:

• a receptacle comprising a plug housing and at least two resilient conductors spacedly provided on said plug housing;
• a replaceable head unit comprising a supporting platform slidably fitted on said plug housing in a detachably attaching manner, and at least two plugging heads which are spacedly extended from said supporting platform and are sized and shaped adapted for fitting into said electric socket, wherein each of said plugging heads has a rear end extended through said supporting platform, wherein when said supporting platform is slid on said plug housing to detachably mount said replaceable head unit to said receptacle, said two resilient conductors are conductively contacted with said rear ends of said plugging heads respectively so as to electrically connect said replaceable head unit with said receptacle;
• and
• a safety arrangement slidably mounted on said replaceable head unit to enclose said rear ends of said plugging heads in a hidden manner, wherein when said replaceable head unit is slid to engage with said receptacle, said safety arrangement is slidably pushed to expose said rear ends of said plugging heads for said resilient conductors conductively contacting thereto.