You can use Ralston Tube Adapters to connect to any brand of tube fitting without a wrench. Simply remove the tube nut and ferrules and thread on the Ralston Tube Adapter. They seal using an integral o-ring so there is no worries about tightening the nut too much hand tight is good enough! They are ideal for use in pressure calibration, hydrostatic testing, pressure safety valve setting or anywhere where a temporary connection to a tube fitting is needed. They are available in brass and stainless steel in a wide range of both fractional and metric sizes.