Final answer:
Receptacle boxes can support different weights depending on the material, design, and installation method.
Step-by-step explanation:
The weight a receptacle box can support for fixtures and trims without independent support depends on various factors such as the material, design, and installation method of the box.
In general, plastic receptacle boxes may support around 10 to 15 pounds, while metal receptacle boxes can typically hold 20 to 25 pounds.
It is important to note that these weight limits are approximate and may vary depending on the specific brand and model of the receptacle box. It is always recommended to consult the manufacturer's specifications or guidelines for the specific receptacle box being used.