How can i increase character length of "Reason" field when submitting the Request in ITSHOP?

Hello Experts,

We have a need to expand the character limit on the "Reason" Field to accomodate additional notes for the users to put in the requests.  Where can i find this?  i tried looking in to Web Designer but was not able to find it.... i did find the VI_ITShop_Approvals but nothing that pertains to the Character limit.

All your help is greatly appreciated.