> For the complete documentation index, see [llms.txt](https://bitmerse.gitbook.io/bpishift-product-spec-sheet/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bitmerse.gitbook.io/bpishift-product-spec-sheet/technical-specifications.md).
# Technical Specifications
| Parameter | Specifications |
| ----------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| Voltage level conversion | Bi-directional
3.3 V <--> 5 V
|
| No. of GPIOs supported
for conversion
| 28 GPIOs |
| Voltage selection | Jumper Connected: Internal 5V from RPi
Jumper Open: External voltage through header pin
|
| External voltage supply range | 3.5 to 5.5V |
| Dimensions | 51.2 x 27.5 x 6.2 mm |
| Weight | 10 grams |
| Operating temperature | 0 °C to 60 °C |
| Humidity | 10% to 95% RH (Non-condensing) |