We Check and Test each single item before sending out, and will return defective items to the distributors/manufacturers for exchange.
Based on the facts that:
We can exchange defective items from the distributors/manufacturers.
Transportation cost is expensive.
The most important fact is that we would pay a lot more, in terms of Cost of Time, if we send out a defective item, because we know you will come back to us and we would waste a lot of time on this if we do so.
Reputation is important to us because we believe Word of Mouth is valuable.
Therefore, why we bother to sell you a defective item? and there is no reason for us to do that which would also damage our reputation. So, don't worry about this.