Bloch line (BL) pair propagations has been investigated by a field-access scheme, applying triangular pulses to a rocking conductor. The stripe domain was stabilized by a current. Current bit confinement initially revealed a bit potential of 0.4 to 1.8 Oe for 2.5- mu m-period tracks. Then noncurrent bit confinement patterns were produced in Co-Pt films with high coercivity (1.5 kOe) and high residual flux density (5 kG). A film thickness of 350 AA produced a bit potential of 1.5 Oe when the spacing between the Co-Pt film and the garnet surface was 1 mu m. Bit-by-bit propagation of a BL pair was achieved with a 5 to 6% bias field margin in a drive field greater than 3.3 Oe.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>