SIIG 4-Port Industrial RS-232 PCI Express Adapter Card (ID-E40011-S1) Supports serial port data transmission rate up to 921.6 KB/s Built in 15Kvdc ESD serial interface protection Built in 256 byte fifo buffer Built in H/w, s/w data direction Flow control Supports Serial port data transmission rate up to 921.6 Kb/s Built in 15KVDC ESD serial interface protection Built in 256 byte FIFO buffer Built in H/W, S/W data direction flow control Warranty: Lifetime limited