What this cradle does in the panel
The LV839334 is the drawout cradle for a MasterPact MTZ2 breaker — it's the stationary frame that stays wired to the bus, so the breaker section slides in and out for swap-out without pulling the panel apart. Rated 800 to 2000 A continuous at 104 °F (40 °C), 3-pole, and UL/ANSI listed with a limiter function for high-fault applications. You don't size this by the breaker alone; the cradle's continuous-current rating matches the breaker frame, and the drawout interface is what lets an MRO crew swap a failed unit in minutes instead of rewiring a line-down shift.
Drawout mounting means the cradle bolts into the switchgear enclosure — the breaker rolls in on guided rails and docks via primary and secondary disconnects. No DIN rail here; this is a bolted-frame install with the panel builder's own bus-bar connections to the cradle's line and load stabs. The 3-pole configuration matches standard 3-phase distribution, and the limiter designation tells you the cradle is built to handle the let-through energy of a current-limiting breaker pair.