What this 74HC126 quad buffer does on your board
The CD74HC126M is a quad non-inverting buffer with independent 3-state outputs, one per channel. Each of the four elements passes a single bit, and the output enable lets you float the pin — useful for shared buses where multiple drivers talk on the same line.
Output drive and what it can't do
Each output sources or sinks 7.8mA, which is typical for 74HC CMOS — enough to drive a handful of CMOS logic inputs or a low-power LED with a series resistor, but not a relay coil or a high-current bus transceiver. If you need more fan-out, plan on a buffer stage or a part with higher drive like the 74ABT family (32mA per pin). The 3-state output is high-impedance when the enable is low, so multiple buffers can share a data line without contention.
Package and hand-solderability
Housed in a 14-SOIC package with 1.27mm pitch, this is a hand-solderable part if you have a fine tip and steady hands — no hot-air gun required. The 0.154-inch body width fits standard SOIC footprints, and the surface-mount profile keeps board height low. No exposed thermal pad to worry about; just route the supply decoupling close to pins 7 (GND) and 14 (VCC).