Scarcity-driven conversion email from footwear retailer Allbirds. Uses countdown subject line ("Going, going...") and inventory warnings ("sizes slipping away") to create purchasing urgency. Gender-segmented CTAs (Shop Women/Shop Men) route customers by demographic while high-contrast buttons emphasize immediate action. Merges FOMO psychology with frictionless segmentation for maximum conversions. Perfect for:
- Limited-stock product launches
- Flash sales with countdown pressure
- Seasonal inventory urgency