Replacement large nut for thumbscrew on embroidery frames.
Swap from the small one to this and you won’t have problems with them working loose again.
LB6770, LB6800PRW, NV1000, NV1200, NV1250D, NV500, NV500D, NV700E, NV750E, NV90, NV900, NV900D, NV90E, NV950D, NV950E, PE700, PE700II, PE750D, PE770, PE780D, SE270D, SE350, SE400