The LC2K0610N7 is a TeSys K reversing contactor from Schneider, rated for AC-3 duty at 6 A up to 440 V — meaning it switches a 3-phase motor load in that current range, with the built-in mechanical interlock for direction reversal. It comes preassembled with the reversing power busbar, so you don't have to wire that crossover yourself.
The LC2K0901B7 is a close sibling in the same TeSys K reversing contactor family — same 3P, same preassembled busbar, same physical dimensions (2.2 in depth, 3.5 in width, 2.3 in height).
The contactor measures 2.2 in (57 mm) deep, 3.5 in (90 mm) wide, and 2.3 in (58 mm) high. The preassembled reversing busbar saves panel space and wiring time — just land the line and load connections.