This is a really useful accessory for grease guns. It is versatile and the ability to adjust the coupler allows access to front end grease fittings in difficult locations.It use has allows me to get to all the fillings on my vehicle without the need to remove the front wheels, as is normally required to access the ball joints.
I have been using these swivel couplers for 40 years, I needed to install some more on different grease guns, so I bought these to complete the changeover