Search around for the shape and size of an existing model in the map you wish to add to. Do a stripper_dump of said map.
Example:
Code:
add:
{
"model" "*289"
"target" "teleexample"
"StartDisabled" "0"
"spawnflags" "1"
"origin" "-123 456 789"
"angles" "0 0 0"
"classname" "trigger_teleport"
}