Most of the garages that supply nitrogen use a grabber/compressor system that strips the oxygen and other bits out of the air and just leaves the nitrogen . My personal point of view is that tyre pressure is much more important that the gas in the tyre, you would be better off spending your money on a accurate tyre pressure gauge.

My new tyres were nitrogen inflated but I won't be dashing back, the Clarke 2.5 hp in my garage at home is a lot easier

A lot of truck fleets use nitrogen, and will have that equipment in their depots and it is making an appearance more and more as the price of the technology drops, you can even get a tyre gun with an in line cartridge to produce the nitrogen, and to be fair , as consumers we are much more price concious and shop around so garages and tyre fitters have to find more ways to make a margin, I mean who ever thought people would be daft enough to buy "ready mixed" screenwash at 5 quid a gallon when the contents are 80% water  2009 GS Auto Zermatt Silver - Sold June 21 after 10 years of ownership

2016 Subaru Outback SE 2.0 diesel SE Premium Lineartronic Sold 2024 after 8 years and 80k miles . Best Car I ever owned !

2023 Toyota Hilux invincible X 2.8 Auto .

MartynB wrote:

............ I mean who ever thought people would be daft enough to buy "ready mixed" screenwash at 5 quid a gallon when the contents are 80% water

H3O even better if you can get it!!!!!!!!!

[quote="Andy131"]

MartynB wrote:

............ I mean who ever thought people would be daft enough to buy "ready mixed" screenwash at 5 quid a gallon when the contents are 80% water

De-ionised water if you please - doesn't go off as quickly, because on one wants algae growing in thier winscreen washer bottle.[/quote

That will be the DI water we produce at 90pence per 1000 litres, then One of our plants makes Original Equipment specification screenwash and antifreeze, plus various brakefluids for a number of very famous vehicle manufacturers and a number of top level brand names ( can't tell you because I would have to kill you !).

when I retire I might start mixing the stuff in my garage and wandering around the supermarket car park filling up screen wash bottles from a backpack at £2 a pop 2009 GS Auto Zermatt Silver - Sold June 21 after 10 years of ownership

2016 Subaru Outback SE 2.0 diesel SE Premium Lineartronic Sold 2024 after 8 years and 80k miles . Best Car I ever owned !

2023 Toyota Hilux invincible X 2.8 Auto .