while they were on a hike in Indiana in February.
Officers believe the man accused of murdering Liberty German and Abigail Williams is 5-feet, 6-inches to 5-feet,10-inches tall, weighs between 180 and 220 pounds and has a goatee.
Their bodies were discovered a day after they went missing.
Police insist their investigation has not gone cold, but after drawing national attention and generating thousands of tips, they still don't know the suspect's name, reports CBS News correspondent Don Dahler.
Investigators hope the new sketch, drawn by an FBI artist, will reignite the public's interest.
"We're gonna get you now. We have a face to go with you," said Becky Patty, Liberty German's grandmother.
German's grandparents think police are one step closer to catching the 14-year-old's killer.
"We want to get this guy off the streets. Know what I mean? Don't want anybody to go through what we been going through," said Mike Patty, German's grandfather.
Investigators released a composite sketch Monday.
"It shows a little more facial features, it gives you a little more information on what we're looking at, who the suspect might be," said Indiana State police sergeant Kim Riley.
German shot it on her cell phone as the alleged murderer pursued her and 13-year-old Abigail Williams.
"If we can get a name or at least a location of this subject, that would be great," Riley said.
The sketch is based in part on a witness who claims to have seen the man around the time the girls disappeared on this railway trail on February 13.
Fear of the suspect apparently kept the witness from coming forward sooner.
"The person was not clear on the color of the eyes, but the person said it was definitely not blue," Riley said.
Police do know what their suspect sounds like thanks to a previously released audio snippet that was recorded by German.
"The likelihood of solving the case is still very high," said former FBI assistant director Ron Hosko.
Hosko says it's unclear how reliable the new sketch is, but at least it forces the public to pay attention again.
"It is just making that connection, it is having somebody's synapses touch and say -- I know who this is," Hosko said.
Police caution the hat the suspect is wearing in the sketch may not be accurate, and are asking the public to instead focus on the suspect's facial features.
The reward in this case is now more than $230,000.