Double ferrule or Single ferrule hydraulic compression fittings?

Single-Ferrule or Double-Ferrule – Which One to Use?

Size: Tube OD 1/2; Male Dia : NPT1/2; Ferrule Mini Inner Dia :1/2 . Material: 304 stainless steel , corrosion resistant ductility at high

Beduan 304 Stainless Steel Compression Fitting Ferrule, 1/2 Tube OD x 1/2 NPT Male, Straight Adapter Connect with Double Ferrules

Double ferrule or Single ferrule hydraulic compression fittings?

VAISHNAVI HYDRAULICS PVT. LTD.

What Are Single Ferrule and Double Ferrule Fittings

Duoloc Single Ferrule Compression Fittings

Instrumentation Tube Fittings, Instrumentation Ferrule Fittings

Single Ferrule Compression Tube Fittings

Fittings 101: Instrumentation Compression Double Ferrule Fittings