Yes CTIS "Central Tyre Inflation System", you can adjust pressures both up and down on the fly. We had a totally enclosed system on the Humvee and I miss it a great deal on the Oka.
I have accumulated most of the necessary bits to fit a similar system to that in the picture to the Oka but will make it easily removeable for scrub country as I reckon it would be easily ripped out but for sand work the system makes it very easy to adjust pressures on the go to suit changing terrain.
OKA 374 LT Van, converted to camper/motorhome,
400ah Lithiums, 1100w solar, diesel cooking heating and HWS,
Cummins 6BT, Allison 6 speed auto, Nissan transfer.
