Raw materials: Ensure that the raw materials used are of top quality. This can be checked from the package of the item you buy. Usage: Ensure that the accessory you buy really fulfils your requirement. Price: Remember that price is not directly proportional to quality and this means that a higher price necessarily need not mean top quality of the item. Certification: Ensure that the item you buy is licensed and fulfils the regulatory requirements as to the quality standards.
Certified manufacturer: Ensure that the manufacturer of the item has the ISO certification. The items that you buy have to be used in the suggested manner. If you buy good quality accessories but use them in the wrong way then they will not give the desired results. It is also better to buy the latest versions of the model as they offer better capacity than the earlier versions. As for the price, it can differ between different manufacturers.