An electrical connector assembly includes a first connector and a second connector. The first connector has a first mating face and a number of first contacts retained therein. Each first contact comprises a first mating board and a second mating board vertically protruding from the first mating face. The second connector is mated with the first connector and comprises a second housing with a second mating face confronting with the first mating face and second contacts. The second housing defines corresponding mating slots to receive the first contacts. Each of the second contacts comprises two pairs of holding arms which are arranged non-parallel to each other and each pair of the holding arm elastically perpendicularly projects in the mating slot thereby clipping one of the first mating board and the second mating board of the first contacts.