Available connector sizes provide 36, 64, 98, or 164 contacts to support x1, x4, x8 , or x16 high speed, serial PCI Express lanes. The SMT connector versions feature 0.1mm lead coplanarity and SMT retention clips at both connector ends to provide additional mechanical strength after soldering. Non-protrusive orientation posts are also available. Users can choose either tray or tape-on-reel packaging for compatibility with conventional SMT board assembly processes. The PCI Express card edge connectors are designed to accept a 1.58mm (0.062″) thick add-in card. A molded polarization key on the connector and corresponding notch on the add-in card prevent improper insertion. Sequential mating for hot plug capability is accomplished by staggering the appropriate edge fingers by 1.0mm on the add-in card.