These subseries come with Step Tracker DW-H5600[3516] GBA-800[5554] GBA-900[5641] GBD-100[3481] GBD-200[3506] GBD-300[3568] GBD-800[3464] GBD-H1000[3475] GBD-H2000[3515] GBX-100[3482] GD-B500[3552] GG-B100[5594] GMA-B800[5555] GMA-S130[5540] GMD-B300[3567] GMD-B800[3486] GPR-H1000[3554] GR-B200[5635] GSR-H1000[3491] GSW-H1000[GSW-H1000] G-Shocks use a built-in 3-axis acceleration sensor to count steps when you walk.