Square D EPD breaker

[rose1981]

Why does square d EPD 1-pole GFCI breaker require two pole spaces?

 

[GoldDigger]

Maybe:
High SCCR/AIC rating takes more space?
Early GFCI circuitry took more space?

 

[iwire]

View attachment 14978

Why does square d EPD 1-pole GFCI breaker require two pole spaces?

Just a small point, that breaker is not a GFCI. that breaker is a GFP.

GFCI is for protection of personal, that breaker is for protection of equipment.

My guess is that it is standard one pole EDP breaker that they added GFP and a shunt trip to by adding a pole space.