Transcend StoreJet 25M3 (TS1TSJ25M3) 1 TB Portable External Hard Drive (Black) on Paytm @ Rs. 3518
https://paytm.com/shop/p/transcend-storejet-25m3-2-5-inch-1-tb-external-hard-disk-black-and-green-cmplxtranscend_storejet25m325inchexternalharddisk_1tb_black-green

Use Promocode HDD800 and Get Rs 800 Cashback.

About Product:-
SuperSpeed USB 3.0 compliant and backwards compatible with USB 2.0
Connection bandwidth up to 5GB/s
Durable anti-shock rubber outer case
Easy plug and play operation, no drivers required
USB powered, no external adapter necessary

price Comparison:-
Amazon @ Rs. 3832
http://www.amazon.in/gp/product/B005MNGQ6C
Snapdeal @ Rs. 3851
http://www.snapdeal.com/product/transcend-external-hard-drive-storejet/42557
Shopclues @ Rs. 3749
http://www.shopclues.com/transcend-storejet-25m3-2.5-inch-1-tb-external-hard-disk-6.html
Flipkart @ Rs. 4499
http://www.flipkart.com/transcend-storejet-25m3-2-5-inch-1-tb-external-hard-disk/p/itmd72p3y3zcsbku