The prices of motorcycle decal and motorcycle protective helmet are climbing.
On Ebay, a group of people were selling $15 worth of the helmets for $1,200.
The prices have gone up in recent days.
On Thursday, someone who goes by the name of Harley Davidson said he sold five helmets for about $4,000.
On Friday, another seller posted $2,500 worth of helmet decals for $3,000, and a third person was selling $1.2 million worth of helmets.
The helmet market has exploded in recent years.
Last year, the American Academy of Pediatrics published a report that found the number of pediatric hospitalizations related to motorcycle helmets rose from 6.3 per 1,000 children to 10.6 per 1.000 in 2015.
In 2015, Harley Davidson sold more than 10,000 motorcycle protective hats.
According to the helmet industry website, the average helmet sold in the United States last year was $9,400.
The helmets that are selling are not necessarily cheap.
On Friday, the eBay motorcycle decaling group sold a helmet for $2.50 on Ebay.