An isolator decoupler comprising a shaft (1), a pulley (2) journalled to the shaft, a torsion spring (10) engaged between the pulley and a carrier (9), the torsion spring loaded in an unwinding direction, a wrap spring (11) engaged between the carrier and the shaft, the wrap spring comprising a cylindrical inner portion (94) and a planar outer portion (93) connected by a tapered portion (155), and the inner portion frictionally engaged with the shaft in a winding direction.