1. For bts 2. Enhance base station sensitivity 3. Widely used in bts coverage 4. Can be used in conjunction with mcpa 5. Commonly used in rural area and township 6. Lightning protection 7. Waterproof, dampproof function 8. Ul by-pass function. Applications In the coverage area of base station, through mobile station to bts, amplify signal to enhance the sensitivity of signal, expand the coverage of bts, improve signal quality.