Siretta direct mount antennas siretta delta2axsmamsra11 sirettas delta 2a is a direct connect stubby antenna tuned to the quad band gsm gprs 3g amp ism frequencies despite its short length of only 535mm it achieves a peak gain of 2 dbi and performs at a high level that most stubby antennas cannot compete with the delta 2a offers a small and compact cable free antenna solution that is ideal for use with wireless terminals within the m2m industry simply screw the antenna into