The slope figure on a robot mower's spec sheet often stops at the edge of the lawn

Robot mowers are sold on a single slope number, and buyers with a sloping garden read it as the machine's limit. In the manuals it is frequently two numbers, and the second one — the slope the mower may take at the boundary of the lawn — can be a third of the advertised figure. Segway-Ninebot's new Navimow H2 series, which reached the manufacturer's European store on 9 February 2026, is rated for 45 per cent inside the working area and 25 per cent at the boundary. The i2 LiDAR declares exactly the same split. Husqvarna is blunter still: the Automower 450X is specified at 45 per cent inside the installation and 15 per cent at the boundary, a threefold difference. Within Segway's own catalogue the split follows the drivetrain rather than the price. The i2 AWD, the cheapest machine in the line at EUR 899, keeps its full 45 per cent right up to the edge. So does the i2 LiDAR Pro at 55 per cent, and so does the flagship X4, which holds 84 per cent — 40 degrees — both inside the lawn and at its boundary. The two models that lose ground at the edge, the H2 and the i2 LiDAR, are the two without four-wheel drive. A better sensor package does not buy traction on a bank. The distinction matters because the boundary is where sloping gardens usually slope. A lawn that falls away towards a fence or a ditch meets its steepest gradient at precisely the point the mower is rated for least, and an owner who checked only the headline number will have bought for the wrong part of the garden. The figures above are all taken from the manufacturers' own specification tables — Segway publishes them only inside the user manuals, not on the product pages.