This TM125D is 4 poles 4d thermal-magnetic trip unit used on Compact NSX 160/250 circuit breakers.This 125A rating thermal-magnetic trip unit is an optimum choice for all distribution applications.It embeds an adjustable thermal overload protection and a fixed magnetic protection against short-circuits.This product is part of our EcoStruxure Power architecture if associated with PowerTag NSX and Compact NSX basic frame.