What does D-D stand for?
D-D stands for "Duct-to-duct"
How to abbreviate "Duct-to-duct"?
"Duct-to-duct" can be abbreviated as D-D
What is the meaning of D-D abbreviation?
The meaning of D-D abbreviation is "Duct-to-duct"
What does D-D mean?
D-D as abbreviation means "Duct-to-duct"