Zip Letters results vs postcards?

[Eric F.]

Hi Everyone,

I recently sent some zip letters from yellowletters.com . They arrived last week and I have not gotten many calls yet. The letters are a follow up to a postcard I sent to the same list so I am unsure if that is why my response rate is lower than postcards or if it is the zip letter themselves. How have you guys found the response rate vs postcards?

My response rate is probably .7 percent. Postcards with this list usually do at least 1.5%, maybe more. 

I had one sent to myself and to be honest it looks like something I would not open, but then again I get in trouble when I apply how I think to a seller.