Easy enough to contact. This was on W4RT's site in the contact area:
W4RT Electronics is a Division of the PanTechne Corporation
Googling PanTechne returns the following:
W4rt Electronics, Pantechne Corporation
3077 Leeman Ferry Road SW
Huntsville, AL 35801-5614 map
Phone: (256) 880-8207
I have no dog in this fight but I find it suspicious that I'd have to search out the parent company to track down somebody instead of the phone number being listed on the website. Why would they create a website and not list a phone number? Just put a note on the contact page that email is preferred like other companies do. Sounds fishy.