# BOM / build overview - Concept 28 R3.1

Use `Fabrication_Part_Schedule.md` for all 93 current fabricated component groups (97 solids total). Each group occurs once per device; multi-body stop-shim groups contain two pieces. Material/process roles and exact STEP filenames are listed there. Do not fabricate bought-in reference bodies as additional custom parts.

| Bought-in item | Qty/device | Source / scope |
|---|---:|---|
| Populated PCB, Flux fb5acde7 | 1 | Supplied manufacturing release and STEP; U6 omitted from supplier STEP |
| SIMCom SIM7670G-MNGV U6 | 1, on PCB | Not a separate enclosure fabrication item; nominal placeholder only |
| Battery Adafruit 2011 | 1 | Protected 2000 mAh pack; verify actual max envelope and lead |
| Speaker CMS-40504N-L152 | 1 | Actual speaker sample and acoustics to verify |
| Microphone Adafruit 3421 | 1 | Bottom-port breakout; use current offset seal |
| LED Kingbright WP154A4SUREQBFZGW | 1 | Four-lead RGB; right-angle clear guide, validate powered output |
| LIDUOLE PTT switch, nominal 6 x 6 x 6 mm | 1 | Dimensions/travel/terminals require physical measurement |
| LIDUOLE volume switch, nominal 6 x 6 x 5 mm | 2 | Same qualification requirement |
| LIDUOLE front switch, nominal 12 x 12 x 4.3 mm | 1 | Same qualification requirement |
| Taoglas FXUB63.07.0150C cellular antenna with cable | 1 | Cellular RF and final routing to verify |
| GNSS antenna / cable | 0 | Omitted for this prototype |
| Woven graphite metal mesh panel | 1 | Nominal 45 x 47 mm blank, R10 corners; cut DXF governs. CAD crossing rods illustrate stock, not separate rod jobs |
| Closure and retainer screws | 18 total | Exact nominal lengths, heads and nylon/metal roles in Assembly_and_Nonprinted_Parts.md |
| Wiring, mating connectors and insulation | As engineered | Electrical harness, lengths and pin assignment require Elian approval; not released by this CAD package |

Foam, contacts, membranes, scrim, adhesive films, dielectric seat and tuning shims are counted in the fabricated-part schedule. Their CAD geometry defines installed nominal shape/thickness; supplier grades, free thicknesses, hardness and attachment are to be selected and qualified. Do not double-order optional shim alternatives or fabricate every tuning alternative for one installed device.

The original supplier electronic BOM, placement list and Gerbers are under `References/PCB_fb5acde7/Manufacturing_Release`. The original `PARTS.md` is a reference; this package records subsequent GNSS, switch-estimate and U6 decisions. No order quantity or purchase is authorized by this BOM.