What size of compression fitting do I need?

It is important to understand the difference between

Compression fitting - Sweat reducing adapters - Master Plumber®

Brass vs Stainless Steel Compression Fittings

Brass Compression Fittings, Size: 1/2 Inch at best price in

PlumbShop Straight Compression Fittings, Chrome, 5/8-in OD x 3/8

Legines Brass Compression Tube Fitting, Union, 1/8 OD

How to Measure Thread Sizes: NPT Fittings, Flare Fittings, and

A Complete Guide to Compression Fittings

SAE Compression Fitting, Size 10 for Size 10 Hose

Dishwasher Supply Line - Installation

180PCS Compression Fittings Assortment kit - 4 sizes (1/4, 3/8

How to Install a COMPRESSION Fitting (PROPER WAY) : 8 Steps (with