Autographed Trump Hats and Books Sold on His Website Were Signed by Machine The items were signed with an autopen machine.

 -- Throughout now-President-elect Donald Trump's presidential campaign, countless money was raised by offering signed items in exchange for a donation.

These items offered on his website, including signed hats and signed copies of his book "The Art of the Deal," were heavily advertised on social media and by Trump himself. But what some buyers may not have realized is that it seems Trump didn't actually sign any of the items available for purchase on his website with his own hand. Instead, the autographs all appear to have been done by an autopen machine, a device used to automatically sign a signature.

The use of an autopen machine only became evident to some after Trump won the election, when opportunists who had purchased such items off Trump's website took to eBay to re-sell what they believed would be a more valuable John Hancock.

What was soon obvious to some was that the Trump-signed hats, offered at various price points during the campaign on Trump's website, including $125, $183 and $243, all appear to be signed in the exact same place -- the lower left of the hat brim, with not a single variance in any signature. Meanwhile, the bookplates in Trump's "election edition" of "The Art of the Deal" -- limited to a run of 30,000 copies, his campaign promised -- featured a slightly different signature from the hat, but again, each book signature appears to be identical.

Whether selling an automated pen signature is disingenuous is a matter of one's opinion of the disclosures made.

On Sept. 12, the signed hats were promoted on Trump's Facebook page. "Only 1,000 Signed Hats! Once They're Gone, They're Gone. Get your signed Trump Make America Great Again Hat before they're sold out!" But when a customer was led through checkout to pay for the hat, a disclosure was made in fine print in a single sentence: "Limited supply of hats which include an autopenned Donald J. Trump signature." The books sold with autographs on Trump's website included a similar caveat as well.

But many say they missed the disclosure.

One man who bought two Trump signed hats for $125 each, says he only found out about the autopen when he listed them for sale after the election and was contacted by an individual who informed him about the caveat. Contacted by ABC News after the item was pulled from eBay before selling, the seller -- who requested anonymity -- said, "I couldn't, in good conscience, sell a hat that I now knew wasn't signed by Donald Trump."

Another man, who said he bought his hat for $183 with the intent to flip it if Trump won, was thrilled when he sold it on eBay for $510. Contacted by ABC News after the sale, the seller said he was shocked.

"I didn't see where it said it wasn't actually signed by him," the seller, who requested anonymity, said. "You think for $183, you have to be getting the real thing. Had I known, not only would I not have bought this, but I'm pretty sure no one would have."

That seller said he is contacting the buyer to see if he wants a refund. "It would be nice if I could also get a refund from the Trump campaign," the man said.

There are currently some listings for hats on eBay that were purportedly signed by Trump in front of people. Those hats have different-looking signatures than the ones sold on Trump’s website.

If a customer who bought a hat or book on the website missed the fine print at the end of checkout, there appeared to be no other signs that they were signed by a machine. Receipts for the hats that came in the mail noted that it was the "official signed hat."

Steve Grad, a long-time autograph authenticator who now works with Beckett Authentication Services, says he has a low opinion of how the Trump campaign marketed the hats. "I can assure you that even if you found the line about the autopen, the general public is not even aware of what an autopen is."

Grad said he has seen signatures of Trump's before that have failed authentication, including ones on items sold in the gift shops of his own hotels. "The crazy thing is, he has actually been a good signer in person, but he also has autographs out there sold officially that weren't signed by him," Grad said.

A lawyer for Trump did not immediately return messages seeking comment. Trump’s spokeswoman, Hope Hicks, also did not immediately respond to a request for comment.

Autopen has long been used by public figures, including presidents, to sign notes and letters. However, it is not common for personalities to sell a product with an autopenned signature.

Production and fulfillment of the hats were done by Ace Specialties in Lafayette, Louisiana, which calls itself a work wear, safety and promotional products company that does most of its work in the oil and gas industry. A call placed and an email written to the company's CEO Christl Mahfouz went unanswered. The Trump campaign paid the company more than $14 million, according to the Wall Street Journal.