A fixed bar that appears on product pages once the user scrolls past the buy box. Keeps the add-to-cart action one tap away no matter how long the page is.
Content
Product image (thumbnail)
Product title
Price
Add-to-cart button
Style
Background color, text color, button style, bar height. Match your theme's primary action button so the bar feels native.
Visibility rules
Show on PDP only — Default. Don't show on collection or other pages.
Show on mobile only — Common — desktop already has the buy box always visible if your theme has a sidebar.
Scroll-distance trigger — Show after the user scrolls past the buy box (typical: 600–800px).
Variant picker
Inline dropdown — Pick the variant directly in the bar.
Open the cart drawer first — Tap opens the cart drawer where they pick the variant.