From Single Bottle to Subscription: A High-CRO Product Page and Pack Strategy for Knockout H2O

Knockout H2O is a performance water brand preparing to launch in 2027, and we are building its Shopify store. This case study covers a conversion-focused product page and a pack and subscription strategy, both still maturing as the launch approaches. The question we set ourselves was simple: how do you turn a product page that only asks for the sale into one that guides shoppers toward the bigger, more profitable order?

Project status: this is work in progress ahead of the 2027 launch. The store is not live yet, so there is no real traffic or order data, and we are not claiming measured conversion results. Content such as the featured review, the guarantee wording and the pack contents is placeholder and will be replaced with the brand's final copy and data before launch. This article is about the thinking and the build so far. You can read about the original store build in our Knockout H2O launch case study.

Before (left) and after (right): the same Pack of 6 product page on a phone.

The starting point: a clean page that leaves the work to the shopper

The original product page was good-looking: a strong hero image, price, quantity, Add to cart and Buy it now, a row of benefit icons and a tabbed description. But for a brand that sells the same water as a single bottle, a 6-pack, a 12-pack and a case, it left the most valuable decisions to the shopper:

• Is it worth buying more than one bottle, and how much do I save?
• Can I subscribe, and what do I get for it?
• Will I get free shipping, and when does it arrive?
• Is it in stock, and is it safe to buy?

How we worked

1. Work on a safe copy. Everything was built on an unpublished duplicate of the theme, named Horizon (CRO). The main theme stayed untouched while we designed and tested, so nothing reaches customers until it is ready.
2. Audit the page against the buyer's questions. We listed every question a buyer has between landing and paying, and checked where the original page answered it, and where it did not.
3. Replace the buy buttons with one buy box. A single custom theme block now holds the purchase decision, so the order of information is designed instead of accumulated.
4. Set up subscriptions. We created a Subscribe & Save plan so the page could sell a real offer.
5. Give every product a job. We decided what each page should push: bundles on the single bottle, subscriptions on the packs.
6. Extend the idea into the cart. We added an upgrade offer to the cart drawer, where the order is about to be decided.
7. Test the real flows. We tested add to cart, subscriptions, stock edge cases and the cart swap on the preview theme, and fixed what broke.

The new buy box

The block replaces the old variant picker and buy buttons. Everything else on the page, the rating, description, benefit icons and tabs, stays as it was.

• Benefit chips under the price (Alkaline pH 8.5, Electrolytes, Zero sugar, Pro tested), so the product's proof points are seen before the shopper scrolls.
• A Subscribe & Save card, preselected, with a 10% saving badge, three short perks and a delivery frequency dropdown. The one-time purchase option sits directly below it, so nobody feels forced.
• Live prices. The card, the button and the totals all update with the purchase option and quantity.
• A low-stock line ("Only 5 left in stock") that only appears when tracked inventory is genuinely low.
• A free-shipping progress bar tied to the store's existing $50 threshold, which counts up for one-time purchases and shows as unlocked for subscriptions.
• A quantity stepper and Add to cart button that shows the live total and switches to "Subscribe & save" when that option is selected.
• Reassurance under the button: a delivery estimate with an order-by countdown, a guarantee line, secure checkout and a featured review.
• A sticky add-to-cart bar that slides in once the main button scrolls out of view.

After: the Subscribe & Save card with per-bottle maths, a one-time option, a go-bigger link and the stock line.

After: shipping progress, a live-total button, delivery promise, guarantee and a featured review.

Subscriptions, set up properly

We created a Subscribe & Save group with 10% off and delivery every 2 or 4 weeks, using Shopify's native selling plans, and attached it to the four water products. We deliberately left it off the T-shirts, because subscribing to a shirt makes no sense and would dilute the offer. The page reads the plan data directly, so the frequency options and the discounted prices always match what checkout will charge.

One lineup, two jobs

Knockout sells the same water as a single bottle and in packs, which creates a strategy question: should every page push a subscription? We decided no. A shopper looking at one $2.99 bottle is not ready to commit to a plan, but they are open to buying more.

• On the single bottle, we push the bigger pack. The subscribe card is replaced by a Stock up & save ladder: Single, 6-pack, 12-pack and a case, each with the price per bottle and the percentage saved against buying singles. The 12-pack is tagged Most popular and the largest pack Best value, and each card links to that pack's page. A line underneath does the arithmetic for them ("Drinking 2 a day? The 12-pack is just $2.58 a bottle, you save $4.89 and can subscribe for even less").
• On the pack pages, we push the subscription. The Subscribe & Save card shows the per-bottle price and the yearly saving against buying singles (for the 6-pack, $2.55 a bottle and about $69 a year), plus a small Go bigger link to the next size up.

The result is a simple path: singles lead to packs, and packs lead to subscriptions.

After: the pack ladder on the single-bottle page, with per-bottle prices and savings.

Before and after, side by side

Pack of 6: the original page (left) and the new buy box (right).

Single bottle: a plain Add to cart (left) versus the pack ladder and cost nudge (right).

Taking the idea into the cart

Many shoppers add several single bottles one at a time. So we added an upgrade offer to the cart drawer: with six or more single bottles in the cart it offers to swap them for a 6-pack, and with twelve or more it offers the 12-pack, showing exactly what the shopper saves. One tap swaps the items and refreshes the drawer.

The cart drawer with 12 single bottles: an offer to swap for one 12-pack and save.

Testing, and what we fixed

A conversion feature that breaks at the last step is worse than none, so we tested the real flows on the preview theme: adding a one-time and a subscription item, switching sizes and purchase options, the shipping bar at different quantities, the low-stock line and the cart swap with twelve singles. That caught a real bug: after the swap, the cart totals were right but the drawer stayed stuck on "Upgrading…". We changed the script to fetch fresh drawer content after the swap and to reuse the theme's own cart event, and re-tested until the drawer refreshed cleanly.

Built to be maintained

• Everything is a setting. Benefit chips, free-shipping threshold, guarantee text, review, colours and the pack ladder's products and bottle counts are all editable in the theme editor, so the same block can be reused on another product or another store.
• It uses native Shopify features (selling plans, inventory, the theme's cart events) rather than stacking apps on the page.
• It degrades gracefully. The subscribe card only shows when a plan is attached, and the low-stock line only when inventory is genuinely low.

Where the project stands

Each element exists to answer a buyer's question or to move them to a bigger order, and that is the pattern we apply to real stores. The store has no real traffic yet, so we are not publishing before and after revenue numbers, and the pack sizes and discounts shown are working figures that will be confirmed with the brand. Once the store is live, we would test this page against the original layout so the lift is measured, not assumed.

Want this on your store?

If your product pages are doing the minimum and you sell the same product in singles, packs or subscriptions, we can map the best path for your shoppers and build it. Book a call and we will look at your best-selling product page together.