Is Office Wear / Business Attire Allowance tax-free

Is Office Wear / Business Attire Allowance tax-free.

  1. What is extent/amount one ca go far?
  2. If no uniform is provided by the company, can one go for keeping allowance by the name of “Office Wear or Business Attire” and will it be tax free.
  3. Any documentation / bills required to ensure this component of salary becomes tax free, when paid on monthly basis.

Thanking in advance,