Paddlewheel Flow Meter, Low Flow, Aluminum Body for Thin Petroleum-based FluidsFLOMEC A1 Series Paddlewheel Meter with Conditioned Signal Output Module (Blind). Select the A1 Aluminum meter when you need an accurate meter for thin petroleum based fluid applications. Conditioned signal module is not FM approved. For low flow applications: 0. 3 3 GPM (1 to 11 L min). Accuracy can vary up to 5% depending on installation and fluid type. Field calibration is recommended for best accuracy.