Overview
The ABB Steel City SB-21-DV Union Dual-Voltage Box is a thermoplastic enclosure engineered for new work applications where both high- and low-voltage wiring must share the same wall opening. The 3-7/16 in. deep backless design eliminates the need to cut electrical boxes and comfortably accommodates large or deep low-voltage devices. An offset bracket keeps the box correctly positioned during installation, and the design allows for proper bend-radius management of low-voltage cabling.
Features
- Dual-voltage capability for combined high- and low-voltage applications
- Accepts a 2-gang faceplate
- Compatible with 3/4 in. Resi-Rings
- Backless design accommodates large and deep low-voltage devices
- Eliminates the need to cut the backs off electrical boxes
- Accommodates bend-radius requirements for low-voltage cabling
- Provides ample space for device installation
- Offset bracket for new work mounting
Specifications
| Attribute | Value |
|---|---|
| Product Type | Dual-Voltage Box |
| Brand/Line | Steel City |
| Material | Thermoplastic |
| Depth | 3-7/16 in. |
| Application | New Work |
| Mounting | Offset Bracket |
| Model | SB-21-DV |
| UPC | 78635800364 |





