Available in 3ds Max 2011 and higher.
<adsk_Utility_Shader_PassThrough>.type : integer
<adsk_Utility_Shader_PassThrough>.type_connected : boolean
<adsk_Utility_Shader_PassThrough>.type_shader : texturemap
<adsk_Utility_Shader_PassThrough>.type_paramName : string
<adsk_Utility_Shader_PassThrough>.TheList : maxObject array
<adsk_Utility_Shader_PassThrough>.Shader_Version : integer