I have sent my calculators in going on 2 months ago and still have not received any payment. They have not called me back and I have not been able to get anyone To answer the phone, PLEASE take your business elsewhere, this is a complete scam. They have an office in Brooklyn for anyone else who this has happened too, check the better business brureau for this adress it's the only sauce I could think of to get your momey. Best of luck.