A connector comprises a first housing having a connection end to be inserted into an opening of a second connector, the first housing containing a first electrical contact, wherein the connection end comprises a first opening. The connector further comprises a first cover biased towards a closed position in which the first electrical contact is inaccessible via the first opening, wherein the first cover is moved from the closed position to an open position exposing the first electrical contact during insertion of the connection end into the opening of the second connector.