This Ecostat Thermostat includes a knob and is a direct replacement for the latest type Aga range cookerDiamond H thermostat. The probe length is about 60mm x 2mm thick. There are 2 male spade connections into ceramic body. Note the silver wire to the probe. This is important as the the earlier version had a copper probe. See here. They are DIFFERENT to the Ranco stat - the probe is thinner and a different material. The Ecostat will fit in place of the Ranco and uses the same wires and mounting bracket. The locking ranco NUT fits the Ecostat shaft. Fitting is actually EASIER as the bulb end is smaller and shorter. Also the AGA TOP does NOT have to be lifted to fit it. For Aga range cookers made in last few years ONLY generally made post 2000 and GD80 and 380G. Please see below for a photo of the Diamond H thermostat that this replaces. If in doubt please check that this is suitable for your Aga range cooker BEFORE ordering.Ranco stat probe length 1400mm.Ecostat probe length 1500mm.Wire connections - same 2 spade male.