4mm Brass Straight Compression Fitting Bulkhead 150 bar DIN EN 1254-2 | Tameson.com
N-UK-4MM-5/32 DOTA 5/32 or 4mm BRASS COMPRESSION FITTINGS 10-pk (A879)
4mm & G1/8'' Brass T-Shape Tee Compression Fitting with Male Threads 150 bar Zinc plated Steel, with NBR insert DIN EN 1254-2 | Tameson.com
Compression Straight Adapter 4mm/ 6mm Lubrication Brass Oil Pipe Fitting For CNC Machine Lubricating System 10pcs/bag - AliExpress
Source Stainless Steel 316 equal tube 3mm 4mm 6mm 8mm 10mm OD Double ferrule union compression fittings on m.alibaba.com
Amazon.com: Joywayus Compression Sleeve Ferrules 4mm Tube OD 2.9mm Tube ID Brass Compression Fitting and Insert Tube Ferrule Kit(Pack of 60) : Industrial & Scientific
Pipe Fitting M5x0.8/M6x1.0/M8x1.25 Male Fit for Tube O/D 4mm/6mm Nickel Plated Brass Air Compression Union Fitting Adapter Straight Connector - (Size: M8/Thread: Fit for Tube OD 4mm) - Amazon.com
R 1/8'' Male x 4mm Brass Straight Compression Fitting 150 Bar DIN EN 1254-2 [2 Pieces] | Tameson.com