The heavy duty feel comes from thicker metal and firm mounting tabs that do not flex under pressure.
Struthers Dunn 219ABA118 Power Relay 24-28VDC 10A 6615661-A2 12-Pin
A nice touch is the gentle resistance on the FTR-F3 model lever, which avoids accidental toggles.
You will find the PHOENIX brand listed in the specs, adding confidence for procurement and maintenance.
The Hella brand on this relay is a nice touch and shows attention to detail overall.
A nice touch is the clear datasheet notes, which help you understand the relay behavior before you finalize your wiring.
With the unbranded/general badge removed, it slips neatly into panels where branding might clash.
A nice touch is that the Square D 8501RS14V20 uses consistent symbols that match common relay guides.
You will find that the Emergency Stop Module is easy to wire and stays put once mounted.
KanSmart is the brand, and it looks like it will last through many cycles without fuss.
What stands out about this relay switch is the clear coil voltage marking on top.