Quote Originally Posted by cory9oh4 View Post
It may say that because the intro doesn't have the runaway safety feature. The intro+ does though. It's like $10 more.
It's because they don't have the "Pulse Proportional" mode that some metal racks require. All herpstat models except the herpstat intro and the herpstat intro + have the "Pulse Proportional" mode , So neither the herpstat intro or herpstat intro + are recommended for ARS/Freedom breeder style racks, though to be honest 9 times out of 10 you won't have an issue.