{{-- Shared definitions for part-number types + the "primary" flag. --}}
<div class="pc-legend" style="background:#f9f9f9;border:1px solid #eee;border-radius:4px;padding:8px 12px;margin-bottom:10px;font-size:12px;">
    <strong><i class="fa fa-info-circle"></i> Part number types:</strong>
    <ul style="margin:4px 0 4px 18px;padding:0;">
        <li><strong>MPN</strong> — Manufacturer Part Number: the code the part's own maker assigns to the item (e.g. a battery's own model <code>BATEFL50L</code>).</li>
        <li><strong>OEM</strong> — the device brand's part code for the same item (e.g. Acer <code>BT.00603.006</code>, <code>LC.BTP01.006</code>). One physical part often has many equivalent OEM numbers.</li>
        <li><strong>Model code</strong> — a short model/family code identifying the part series.</li>
        <li><strong>Internal</strong> — your own company/internal reference code.</li>
        <li><strong>Other</strong> — anything that doesn't fit the above.</li>
    </ul>
    <strong>Primary:</strong> marks the single headline identifier for this product — it's highlighted in the product view/modal and listed first. Tick it for the one number you'd quote as "the" part number; leave the rest unticked.
</div>
