Small Thumb Screw, Brother #XC5817051
Guaranteed to fit Babylock Sewing Machine Models:
BMP6, BMP8, BMP9, BMV10 Valiant, BMY6, BND9, BNT10, EMP6
Guaranteed to fit Brother Sewing Machine Models:
PR1000, PR1055X, PR600, PR600II, PR600C, PR620, PR650, PR650C, PR680W
The Large Thumb Screw (#XC5817051) can be found here.