Set of 6 Brand New No-Back-Lash Pig-tail Bobbins Cases for Embroidery machines. The Bobbin Case compatible part number #541678NBL. These are "L" size bobbin cases. These bobbin cases will also fit many models of Embroidery Machines using "L" size bobbins (Bobbin Diameter measures 21MM). These top class NBL (No-Back-Lash) bobbin cases are designed with a brake spring which puts constant, light pressure on bobbins to overcome momentum. Bobbins stop spinning faster, preventing unraveling or tangling of bobbin thread when sewing operations stop and start. Following are the partial list of sewing machine models that these bobbin cases fit : Alphasew : P20U33-3 Artisan : 20-3, 20-53, 20U-143 Barudan : BEAM, BEL, BELL, BEM Brother : B651, B652, TZ1, XL622, XL702, XL703, XL2005, XL4001, XL5001 Happy : HCM, HM4, HMF, HMS, J-4, J-7, J-8, K-4, K-7, K-8 Meistergram : M100, M600, M700 Singer : 20U, P20U33, P20U143 Tajima : TM, TMB, TMBE, TMBW, TME, TEMEF, TMEG, TMF