Pneuflex' s SPL 04-02 model is stainless steel male elbow push in fitting with 4mm O.D connector and R, PT, BSPT 1/4 male thread. 4mm tube x R 1/4 thread male elbow is used to connect 4mm tube at a 90° angle to a female thread and tightened with a flat wrench. All body are made of high grade 316 SUS and it can be rotated after installation.