Windows phone unlocked no cracks, works perfect two sim card slots...

BLU W510U

Highlights

GSM / 3.5G HSPA+ Capable

1.2 GHz Snapdragon 200 CPU

8GB Storage Capacity + 1GB of RAM

5.0" IPS LCD Display

1280 x 720 Resolution

8MP Rear Camera + 2MP Front Camera

microSDHC Expansion Slot

Dual SIM Card Slots

Windows Phone 8.1

Features

The unlocked, pink Win HD W510U 8GB Smartphonefrom BLU features dual SIM card slots, making it possible to utilize each slot for a different phone number. You can program two different phone numbers to this phone to help avoid roaming charges and eliminate the need to purchase a second phone. 

The Win HD is powered by a 1.2 GHz Snapdragon 200 processor, complete with 1GB of RAM