1. The stability of reliability work is the first choice for alarm equipment. The only evidence of stability is the engineering example and the user's response. 2. Convenient to use For users, the less knowledge and operation steps, the better. 3. Function Alarm equipment does not pursue multi-function, the more functions, the easier it is to malfunction during use. 4. Reasonable price This does not mean the lowest price, but depends on the best product the consumer can accept within his affordability. Partial Reflector,Dual High Reflectors Mirror,Triple High Reflectors Mirror,High Reflector Mirror Lambda Research Optics ChangChun,LTD. , https://www.lambdachina.com