1 Kg DRAW BAR To fit both LGB / G Scale Non-Polarized Magnetic Coupling Contains - 1 pair MAGNETIC COUPLINGS PIVOTING Non-polarized for Standard gap between rollingstock. There is no A & B end these couplings will work either way round that you place your rollingstock / locos guaranteed mating no fuss. Will mate with other Porter House magnetic couplings. See last picture.