The Siemens 3RT1015-2BW44 is a SIRIUS power contactor in size S00 — the smallest frame in the SIRIUS family — rated to switch 10 A at 24 V DC on the main contacts. Spring-loaded terminals on the main current circuit accept 2x (0.25 to 2.5 mm²) solid or stranded wire, which saves a turn on the screwdriver during panel build.
The 45 mm width and 60 mm height keep it tight on the DIN rail — you can side-by-side mount multiple units without derating for heat stacking, as long as the ambient stays within -25 to +60 °C during operation. Depth is 114 mm, so account for that when laying out the enclosure depth against the gland plate.