Because searching their online catalog can be weekend long rabbit hole,
Here's a link to the fittings I've been using for the last decade+,
McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com
They say for copper but work just fine. I've used them w/ & w/o inserts in the tubing.
And what they look like/order number,