Saint Dismas was the Good Thief who was crucified with Jesus. Dismas rebuked the other thief crucified at the same time (Gestas). And, Dismas asked for Christ's blessing. Because of that, he is the Patron Saint of those condemned to death. He was raying for redemption during the Crucifixion of Christ.
There is also an old Arabic legend that tells the story of the Holy Family running to Egypt for safety. During their journey, they were accosted by a band of thieves, including the two who would be later crucified with Jesus - Dismas and Gestas. The legend tells that Dismas realized that there was something special about the Holy Family and convinced the accompanying highwaymen to leave the family alone.
Our medal is made of silvery metal in Italy. On the back it reads,
PRAY FOR US
It measures 1 inch high (a little bit longer becuase of the hanging hole) and it is 5/8 inch wide.
Two medals are shown to illustrate the front and back.