A minimum of .020" (0,50 mm) is usually required, from the bottom of the lead to the bottom of the insulator, to assure adequate room for board cleaning and solder joint inspection. Standoffs are not required on surface mount interconnects with large cross-section tails. The connector leads sit on the board rather than passing through it providing the necessary stand-off. Leads that are at least 0.020" (0.50mm) in thickness have adequate structural strength to handle normal insertion and withdrawal without distortion. However, many micro sockets have leads that are only .005" (0,13mm) thick. For leads with these small cross sections, standoffs built into the insulator are recommended to absorb the stress of insertion. Additionally, they help protect the solder paste from being displaced off of the pad during placement.solder joints.