> ## Documentation Index
> Fetch the complete documentation index at: https://popup.apps.madvalley.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Selling Products

> PopUp adds items to the Shopify POS cart, where you can complete the transaction.

## Weight-based sales

1. Open the PopUp tile in Shopify POS
2. Find the product (browse by category or search)
3. Tap the product tile
4. A keypad appears — enter the weight of the item
5. Tap **Add to Cart**

PopUp multiplies the weight by the price per unit and adds the correct line item to the Shopify cart. From there, check out as you normally would in POS.

### Supported units

Each product is set to one unit: **lbs**, **oz**, **kg**, or **g**. The unit is set when you create the product and shown on the product tile in POS.

### Weight entry modes

When you open a weight-based product, a toggle appears in the top-right corner of the entry screen. You can switch between two modes:

**% w/w (decimal)** — Enter the weight as a single decimal number. The digits after the decimal are a fraction of the larger unit.

* Example: `0.73` for a product priced per lb means 0.73 lbs
* Best for digital scales that display a single decimal reading (e.g. `0.73 lb`)

**lb/oz or kg/g (compound)** — Enter the weight as a compound reading. The digits before the decimal are the larger unit, and the digits after are the smaller unit directly — not a fraction.

* Example: `2.5` in lb/oz mode means 2 lb 5 oz (not 2.5 lbs)
* Example: `1.350` in kg/g mode means 1 kg 350 g
* Best for kitchen or deli scales that display a compound reading (e.g. `2 lb 5 oz`)

The display on screen updates as you type, so you can confirm the reading before adding to cart.

**Which mode opens by default** depends on your [Weight mode default setting](/docs/settings/weight-mode-default). The POS also remembers the last mode you used for each product on that device — so if you switch a product to lb/oz mode, it will open in lb/oz next time on the same device.

Products priced per unit (not by weight) do not show the toggle.

## Fixed-price item sales

1. Open the PopUp tile in Shopify POS
2. Find the product
3. Tap the product tile — it's added to the cart immediately at the set price

## Mixing weight and fixed-price items

You can add weight-based and fixed-price products in the same cart. Each adds as a separate line item.