1.Why do my products arrive at room temperature when the indicated storage temperature is 2°C ~8°C or -20°C?
If the products are delivered at room temperature, it means they are stable during shipping and proper handling. Normally, storage in the refrigerator or freezer is only required for long-term storage and products in powder form can store up to 2 years at -20°C

2. Do different batches of a product always look the same?
Occasionally, different batches of the product may look slightly different in color and appearance. But it will not affect purity, quality or performance of the product. 
3. Why my product can hardly be seen in the vial?
Sometimes, product in small quantities can easily attach to the wall of vial, so the vial looks almost empty. Make sure the product is completely dissolved with the right solvent using vortex or sonication.