---
title: "Product page and installments"
url: https://phatdev.net/en/docs/tandoanh-theme/trang-san-pham
lang: en
updated: 2026-10-20
alternate:
  vi: https://phatdev.net/docs/tandoanh-theme/trang-san-pham
markdown: https://phatdev.net/en/docs/tandoanh-theme/trang-san-pham.md
---

# Product page and installments

Part of the doc set: [Tân Doanh](https://phatdev.net/en/docs/tandoanh-theme.md)

> Variation-based gallery, stock states, sticky bottom buy bar, and the installment calculator module.

## Product page
- **Gallery + lightbox**, with images that switch to match the selected variation.
- **4 stock states** including pre-order, shown clearly before the customer taps buy.
- **Sticky bottom buy bar** on phones, so the price and buy button are always visible.
- Tabs for description, reviews and **Q&A** (questions are held for moderation, with spam protection and rate limiting), plus related and recently viewed products.
- **AI Performance tab** for graphics cards: compares AI and rendering performance (OctaneBench, V-Ray) against models in the same segment.

## Installment calculator
- Applies to products priced at 3 million VND or more.
- The fee table by bank and term is configured in the **Trả góp** (Installments) tab of the admin area.
- Customers see the monthly payment, the total fee and the difference compared with paying in full.

## Cart and checkout
- The cart slides in from the right and updates via AJAX, with no page reload.
- Checkout is tuned for Vietnam: two-level Province / Commune addresses following the 2025 standard.
- **VAT invoice**: enter a tax code to auto-fill the company name and address.
- Turn discount codes, gift packaging and the promotion sign-up form on or off in the **Thanh toán** (Payment) tab; the promotion email list can be exported as CSV.