Guide with Terms and Conditions:
How to Use: Visit store.steampowered.com/redeem or open the Steam client. Sign in and enter the gift card code in the ‘Redeem a Steam Wallet Code’ section to add funds to your wallet.

Terms and Conditions: Valid for 12 months from the date of purchase. Redeemable only on Steam India store and official Steam applications. Not refundable or exchangeable for cash. Cannot be combined with other promotional offers. Funds added once redeemed, and are non-transferable. For support, contact Steam customer service.