Why a board-mount SSR in this slot
The Omron G3M-B202PEG4DC20MA is a PCB-mount solid state relay from Omron's G3M line, built to solder directly onto a control board rather than plug into a socket or snap onto DIN rail — that footprint is what you reach for when the load switch needs to live inside the same enclosure as the logic it drives, with no socket wiring to fault.
Where the G3M-B202PEG4DC20MA sits in a panel
A PCB-mount SSR of this class goes inside a control board that switches an AC or DC load — heating elements, solenoid valves, indicator lamps, small motor starters — wherever the cabinet designer wants zero moving parts and silent switching on the logic board. Because it solders to the board, the relay's creepage and clearance ratings travel with the PCB layout; the panel-side wiring is the load and control terminal side, not the relay socket, so derating discussions center on the board's copper area under the output tab and the ambient inside the enclosure.
Omron classifies this part as a mature lifecycle stage on the official record, so it is still orderable but no longer a flagship new-design push — typical practice is to confirm stock and last-buy windows at quote time, and to design the next board spin with a supported alternate already mapped.
Sourcing posture for the buyer
For a maintenance spare on a line where the existing board is already designed around this footprint, that quoting channel is the realistic route — no immediacy promise is made, and lead time is whatever the quoted lot carries.