The chains make up the bulk of the total polygon count (approx. 90%) and can easily be removed if poly count is a concern for you.
Available in both .FBX and .OBJ formats.
There are two sets of textures included in both; one is for PBR workflow (Base Color, Height, Metallic, Normal, Roughness), the other is packaged for use in Unreal Engine 4 (Base Color, Normal, OcclusionRoughnessMetallic).
How to use the UE4 texture set: The 'OcclusionRoughnessMetallic' map contains information for all 3, but on separate channels. Red=Ambient Occlusion Green=Roughness Blue=Metallic