Bruteforcing WPA

[Swirnoff]

Hi! I'm trying to bruteforce a WPA hash with cudaHashcat-plus, and I'm suspecting the key to be a phone number. I'm only making this assumption based on the fact that most WEP networks that I cracked in the past use phone numbers as their wifi keys. Here it's a 10-digit numer, including the 3-digit area code. So how do I properly create a mask and charset strings, if for example, the first 3 digits are 707, followed by the rest of the phone number (707xxxxxxx)?
In other words, what exactly do I plug into the Mask and Charset1?
Is it "707?d?d?d?d?d?d?d" for the Mask; what about the Charset?

Thanx for your help in advance, because the manual is a bit confusing on the subject.