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metal Box

FS Box 2-Gang

Double gang FS box for outdoor dual device installations.

24

cu.in. Volume

12

Max 14 AWG

10

Max 12 AWG

4" x 4" x 2"

Dimensions

Conductor Capacity per NEC 314.16

Maximum number of conductors that can fit in this 24 cu.in. box based on wire gauge (not accounting for devices, clamps, or grounds).

Wire GaugeVolume EachMax Conductors*
18 AWG1.5 cu.in.16
16 AWG1.75 cu.in.13
14 AWG2 cu.in.12
12 AWG2.25 cu.in.10
10 AWG2.5 cu.in.9
8 AWG3 cu.in.8
6 AWG5 cu.in.4

*Theoretical maximum for conductors only. Actual capacity will be less when including devices, clamps, and grounding conductors.

Common Applications

Dual outdoor outlets
Outdoor switch/outlet combo

Calculate Box Fill for FS Box 2-Gang

Use our free calculator to verify your FS Box 2-Gang meets NEC 314.16 requirements.

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Similar Box Types

4" Square x 1-1/4" Deep

4" x 4" x 1-1/4" • 18 cu.in.

4" Square x 1-1/2" Deep

4" x 4" x 1-1/2" • 21 cu.in.

4" Square x 2-1/8" Deep

4" x 4" x 2-1/8" • 30.3 cu.in.

4-11/16" Square x 1-1/4" Deep

4-11/16" x 4-11/16" x 1-1/4" • 25.5 cu.in.

About the FS Box 2-Gang

The FS Box 2-Gang provides 24 cubic inches of volume for electrical connections. This metal box is commonly used for dual outdoor outlets, outdoor switch/outlet combo. With dimensions of 4" x 4" x 2", it offers adequate space for most residential and light commercial applications.

Box Fill Calculation Example

For a typical installation using 14 AWG conductors:

  • Box volume: 24 cu.in.
  • 14 AWG conductor volume: 2.00 cu.in. each
  • Maximum conductors (theoretical): 12

Remember to account for devices (2× conductor volume each), internal clamps (1× conductor volume), and equipment grounding conductors (1× conductor volume for all grounds combined).

Practical Example: Receptacle Installation

Installing a duplex receptacle with two 14/2 NM cables in this box:

  • 4 × 14 AWG conductors = 4 × 2.00 = 8.00 cu.in.
  • 2 × grounds (count as 1) = 1 × 2.00 = 2.00 cu.in.
  • Internal clamps = 1 × 2.00 = 2.00 cu.in.
  • 1 × receptacle = 2 × 2.00 = 4.00 cu.in.
  • Total: 16.00 cu.in.

Result: 16.00 cu.in. ≤ 24 cu.in. = COMPLIANT

Related Resources

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