This is a DU-BRO .25-.50 2-Cycle Glow Engine Vibration Reducing Motor Mount.
Length of each arm : 1.5 in.
Overall Length of Mount : 2-3/8 in.
Distance between the firewall mounting hole centers top to bottom : 1.56 in.
The distance between the firewall mounting hole centers left to right is determined by how far apart the left & right mount halves are mounted.