Popular 8.5x3" tyre suits 5.27 inch rims such as those on Zero 9 series, VSETT 9 series (9/9+), eScootNow G15 Commander and G20 ProMax 8.5 Pro.
Typically fitted to Zero 9 series (including as uplift from 8.5x2). Also suitable for VSETT 8 (front as rear is 200x60 solid) and VSETT 9 series (9/9+). Mixed reports on suitability on Zero 8 (front as rear is 200x60 solid) although likely fits. Will not suit Zero 8X (200x90 solid) and VSETT 8+ (200x60 solid rear and now front). Also used in the iScoot Bexley 8 & 9 and Machine Vixen Light. Check the length of your valve stem, often the CST 8.5x2.00-5.5 tube is used as the valve stem protrudes out slightly further.
Observed internal diameter 132mm (~5.2 inches). Width at bead: 37mm.
Nameplate tyre pressure: 45PSI. Letting pressure drop to <40psi will significantly increase likelihood of pinch punctures with tyres of this size.