Vector mail icon

Here are a few vector mail icon designs:

1. Simple Envelope Icon

<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <rect x="2" y="2" width="20" height="20" rx="2" fill="none" stroke="currentColor" stroke-width="2"></rect>
  <path d="M10 12L14 16L18 12" stroke="currentColor" stroke-width="2"></path>
</svg>

2. Mailbox Icon

<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <rect x="2" y="2" width="20" height="20" rx="2" fill="none" stroke="currentColor" stroke-width="2"></rect>
  <path d="M10 12L14 16L18 12" stroke="currentColor" stroke-width="2"></path>
  <path d="M10 4L14 8L18 4" stroke="currentColor" stroke-width="2"></path>
</svg>

3. Email Icon with Arrow

<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <rect x="2" y="2" width="20" height="20" rx="2" fill="none" stroke="currentColor" stroke-width="2"></rect>
  <path d="M10 12L14 16L18 12" stroke="currentColor" stroke-width="2"></path>
  <path d="M10 4L14 8L18 4" stroke="currentColor" stroke-width="2"></path>
  <path d="M12 12L16 16" stroke="currentColor" stroke-width="2"></path>
</svg>

4. Envelope with Stamp Icon

<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
  <rect x="2" y="2" width="20" height="20" rx="2" fill="none" stroke="currentColor" stroke-width="2"></rect>
  <path d="M10 12L14 16L18 12" stroke="currentColor" stroke-width="2"></path>
  <path d="M10 4L14 8L18 4" stroke="currentColor" stroke-width="2"></path>
  <path d="M12 12L16 16" stroke="currentColor" stroke-width="2"></path>
  <path d="M12 12L14 14" stroke="currentColor" stroke-width="2"></path>
</svg>

These are just a few examples of vector mail icon designs. You can customize them to fit your specific needs and style.