The primary function of a trademark is to distinguish the commercial origin of your product. Trademark registration is made under 45 different classes based on the various kind of products and services the trademark applicant provides.
India follows the NICE Classification system which brings consistency, making trademark search more manageable for the applicant.
Related: Trademark Classes
Identical or similar marks within the same class have a high risk of causing customer confusion, and hence protection is not granted to such marks.
Hence, a finished product theoretically is classified according to its function or purpose which is provided in the list of classes by the government.
To Illustrate, Shahrukh Khan has file trademark application in all of the trademark classes. Whereas, Google, Apple and Disney chose classes which they considered relevant for their product.
The goods or services appearing in the classes are general indications relating to the fields to which, the product belongs. The explanation for trademark will be one of the factors while determining whether the mark will infringe upon the mark registered or not.
Before you attempt to file a trademark application, you will have to narrow down your selection based on the fact, whether you provide goods or services.
The purpose of a finished product is what will be the deciding factor while choosing the class from the classified analogy indicated on the government site.
If the function of the product is not mentioned in of the class heading, you could select the class based on other comparable finished products.
The second step will involve concluding that the mark will be for the whole of the company or a single line of merchandise. This would determine that the trademark registration will be filed for a single class or multiple.
Description of your product will determine whether the trademark examiner will consider your brand to be confusingly similar to the mark already registered. Hence, it is recommended to enlist the help of a trademark expert who is well versed with the trademark registration process and drafting of the application.
Nice classification may be extremely useful but completely relying on the class number is never a good idea. The reason is that there is some degree of overlap between the classes.
For instance, while searching for "telecommunication" in the list of classes, the trademark class selecter list class 9, class 37 and class 38 or for a case when registering a trademark for alcoholic beverages the class for beer is different.