A bellows contact structure benefits from improved spring characteristics and provides double contact points for better reliability. Bellows contacts are formed by bending metal (rolled surface), resulting in contact flexibility that offers high resistance to torsion, shock and vibration. In addition to increased drop resistance, rolled surface contacts offer low insertion force and improved retention durability. By comparison, a standard tuning fork design is shaped by die-cutting, resulting in more rigid spring characteristics. Drop impacts are more readily transferred to the contact which contributes to solder cracks. Additionally, cut out surfaces rub against one another, accelerating the wear on plated surfaces.