Add a high speed rs 232 serial port to your laptop computer via an expresscard expansion slotr r the high performing single chip design optimizes speed reliability and power while reducing cpu load by as much as 48r compatible with both 34mm and 54mm expresscard slots includes a slot spacer for greater security while installed in 54mm slotsr r the ec1s952 1 port native expresscard rs232 serial adapter card with 16950 uart lets you add an rs232 serial port to your laptop or expresscard equipp