Today AESA antenna is becoming more popular in various systems and for further use of it, lowering cost of key component like TR module is crucial. In this paper, a design of a low cost X band GaN module is described. In this module, all devices including HPA are surface mounted on resin board with highly enforced heat dissipation method inside resin. Furthermore unique anti-radiation property with EM shielded devices, enabling coverless module is adapted. The prototype module exhibits 13.3W output power with 30.8% efficiency at X band. Operational Isolation between channels is 29dB with coverless configuration. It weighs only 8.5g per channel, and it's manufacturing cost is estimated to be 40% of our conventional GaAs module.