A trade catalogue is not browsed. It is searched, by somebody who already knows roughly what they want and is confirming it exists and what it costs.

This guide covers searchability, the page-per-product decision, and prices.
Searchable text is the whole thing
A flipbook or a scanned catalogue is a sequence of page images. There is no text in it, so there is nothing to search.
The buyer with a part number pages through looking. After thirty seconds they call a supplier whose catalogue answered immediately.
Real text on real pages is searchable both within the page and by search engines, which means a buyer searching a part number can reach your catalogue without knowing you exist. That second effect is larger than most suppliers expect.
One page per stock code
Each product at its own address.
Found in search on its own terms. Sent to the person who approves the purchase without instructions about page numbers. Carrying the specification, the variants, the lead time and the price in one place.
The catalogue becomes the index: categories, a search, and a way to browse for people who want to.
| Catalogue as one file | Page per product | |
|---|---|---|
| Search a part number | Not possible | Instant |
| Found by search engines | Rarely | Per product |
| Send one item onward | A page number | An address |
| Price correction | Republish | One page |
| Discontinued handling | Reprint | Mark and redirect |
Prices that move
If prices change more than annually, keep them off the product pages and on a linked price page.
Then a price change is one edit rather than a republish and a scramble to tell everyone the previous version is wrong.
Whatever you choose, keep the catalogue address permanent. That way a correction reaches every buyer holding the link, including ones you have lost track of.
Discontinued is not deleted
A buyer bookmarked a product two years ago and wants to reorder.
If the page is gone they get an error, with no indication of whether it was replaced or by what. That buyer was as close to ordering as buyers get.
Mark it discontinued at the top, say when, and link to the current equivalent. The old bookmark now does more than it did before.

Photography
Product photographs are the weight in a catalogue.
Serve screen-sized versions on listing pages with a larger version on the product page and full resolution on tap. Load images below the fold only as the buyer scrolls.
A catalogue that takes six seconds to become usable loses buyers who were going to order, and the fix is entirely in image sizing.
Keep the printed catalogue useful
Printed catalogues still work at trade shows and sit on shelves at long-standing customers.
The problem is the shelf copy being quoted from years later. Printing the address on the cover and each section turns the paper into a route to current information rather than a record of old prices.
For the surrounding ground, see How to publish an online catalog and How to share a catalogue as a link.
Put it at an address
Use real searchable text, give every stock code a page, keep moving prices on a linked page, mark discontinued items rather than deleting them, and print the address on the paper version.
Then the buyer with a part number finds it before calling someone else.