SizeEcho shows apparel merchants which products and sizes run too small, true to size, or too big, using buyer answers after an order ships. After fulfillment it waits a delay you set, then sends one event to Klaviyo. Your Klaviyo Flow emails the fit check-in. Answers land in Overview, Products, and Sizes so you can improve size guides and product copy. Requires Klaviyo. SizeEcho does not email buyers itself. Billing uses Shopify Billing.

• See which products and sizes run small or large from buyer fit answers
• After shipping, send a fit check-in through your Klaviyo Flow
• Buyers pick too small, true to size, or too big (optional reasons)
• Review answers in Overview, Products, and Sizes to fix size guides