There models are part a set of Huge Sci Fi Turret Pack all with three levels of details (LOD) on the Unity assets store .
Contents:
16 Unique turrets
18 Hexagon tiles
3 Skyboxes
57 Prefabs
3 LODs for each turret
3 PBR Texture sets 2048 x 2048
All setup, animated and ready to go
Great care and time have been put into these high quality turrets. The materials are baked from high poly models for best results. Materials contain 2048 x 2048 maps, including Albedo, Metallic, Normal.