According to one embodiment, a fastener comprises a first side and a second side opposite the first side. The first side is connected to the second side thereby forming a U-shaped structure. The fastener further comprises a bottom portion wherein the first side and the second side are connected, and a top portion opposite the bottom portion. The first side comprises a first engagement spring. The first engagement spring is connected to the first side in the vicinity of the bottom portion. The engagement springs have inward facing gussets connected to the bottom portion. The second side comprises a second engagement spring. The second engagement spring is connected to the second side in the vicinity of the bottom portion. A cavity is formed between the first side and the second side as will be described below. The engagement springs include an engagement region operable to adapt to variations or movement of a slot.