Ps 150
It's definitely not the right foot..Mine has a silver bar that rest over the screw..The one for my machine on the singer site is all white..
And trust me Chele no amount of lifting the foot, gentle persuasion, pushing, shoving nor teary eyed cussing would let me "slide" that sandwich under there smoothly, much less have a smooth sewing experience lol...I wanna go yell at that "professional viking salesman"