The Ring RAC635 is one of the cheapest tyre inflators you can buy that offers this level of automation. All you have to do is screw the air hose connector on to your car wheel tyre valve, set the unit to your desired tyre pressure / PSI level by literally turning a knob that’s on the front of the unit, pressing the power button (On), and that’s all you need to do. The Ring RAC635 compressor will pump up the tyre to the manual or pre-set PSI level you have chosen and then very conveniently automatically turn itself off once the task is complete. It’s a fool-proof operation, and it’s designed that way so that even drivers with limited or no knowledge about cars, especially when it comes to pumping up tyres, can independently carry out this procedure without a hitch.
The previous model Ring Tyre Inflator, the RAC600, also has the option to inflate tyres using similar automation. Although, the RAC635 is slightly easier to set due to the turning of just one dial. But in saying that, once a PSI is known they are both very easy to use because you can store (pre-set) a tyre pressure in the memory bank of the inflator so that it remembers it for next time.
Both models have won awards, and both are suitable for car tyres, motorbike tyres, and bicycle tyres. The two models are powered by your cars 12v DC cigarette lighter / auxiliary socket. And they each have a clear blue digital screen (although the 635’s is bigger), extra attachments for pumping up other items like footballs, carry case, and built-in white and red LED lights. Red to be used for emergency / warning light and white for making pumping up tyres in the dark do-able without the need for another light source. The price difference between the two models is minimal.
The Ring RAC635 is the upgraded model and does have some slightly better features. It inflates tyres a little faster. From a tyre being completely deflated, up to 35PSI in less than 3 minutes. All cables are longer. The power cable is 3.5 meters and the air line is 70 centimeters. And the RAC635 comes with 3 extra attachments rather than two for the RAC600. The PSI limit of the RAC600 is stated as 100PSI. However, as written about already in the RAC600 review on this website, that limit is slightly exaggerated. The RAC635 has a maximum PSI level of 80 PSI, but that is considered by most to be a more accurate representation of the products compression limit.
Reviewers have left comments stating that this item has inflated to 65 – 70+ PSI without a problem. One thing to be aware of if inflating 1 + tyres from flat in the same sitting is the depletion of power it may have on your car’s battery. To not end up with a flat car battery its recommended that you use the Ring RAC635 tyre inflator while the car’s engine is running to prevent any issues with a flat battery arising.