Xteink X4 device model

## Overview
This is a precise 3D reference model of the **Xteink X4** compact e-reader ([Product Link](https://www.xteink.com/products/xteink-x4)).

I created this model using digital calipers to ensure a perfect fit for accessory design. If you are looking for a protective case for this device, you can find my design here: [Xteink X4 Case on Thingiverse](https://www.thingiverse.com/thing:7287943).

## Technical Accuracy & Measurements
Please note that these dimensions are based on **actual physical measurements** rather than the official manufacturer specifications. The X4 has complex side curvatures that vary along the length and width.

**Comparison:**
* **Official Specs:** 114 mm x 69 mm x 5.9 mm
* **Model Dimensions:** 114.2 mm x 69.2 mm x 6.2 mm (measured at the widest/thickest points)

## Source Files (Onshape)
This model was created in Onshape and is public. You are welcome to copy, branch, or "tinker" with the design parameters directly:
[Onshape Reference Model Link](https:/