The D3 class was a type of destroyer starship in service to the Imperial Klingon Defense Force in the 22nd and 23rd centuries. Its appearance was best characterized as a stunted version of the more familiar D7 design. (ENT novel: Rosetta; ST video game: Legacy) Based on appearance and relative strength, the D3 is a likely candidate for the identity of the unnamed Klingon scout vessel class seen on several occasions.