This is a set of three lab monitors with advertisement of THINKINGWITHPORTALS.COM

To use it in your map :
 1. Copy the folder "twp_lab_monitors" with texture files to portal 2/portal2/materials
IMPORTANT to have the textures in that path.
 2. Copy the folder "twp_lab_monitors(ins.)" with instances to portal 2/sdk_content/maps/instances
 3. In HAMMER creat an entity func_instance, in VMF Filename browse to the file you want 
in path portal 2/sdk_content/maps/instances/twp_lab_monitors(ins.)
 4. Pack the texture files (.vmt and .vtf) of the instances you used with Pakrat or BSPZIP. 