BQWB3236 Panel with Limiter Space, Slim Panel Compact 21, Horizontal 1-Row, Surface Mount, 6+0, 30A Main Breaker Capacity: 30A Material: Plastic Series/Specification: Slim Panel Compact 21, Horizontal 1-Row Type Without Door Phase System: Single-Phase 2-Wire Number of Circuits + Circuit Spaces: 6+0 Dimensions (mm): H245 x W350 x D53 Limiter Space: Included Shape: Surface Mount I installed it, but I never used it. There is no box or instruction manual, so please check online.