The paper considers gas movement through an annular packed bed bounded on two sides by unobstructed distributors. The design permits a substantial reduction in pressure difference. Measurements and predictions are compared. CFD codes have been adapted to give the Brinkmann-Forscheimer extended D'arcy equation within the porous areas and the standard Navier-Stokes equations apply in free flow areas. Measured pressure differences across the porous bed are as predicted. In addition, an indicator of skewness is defined to account for maldistribution. This is a difficult measurement due to pressure differences as low as 4 Pa. Nonetheless, reported values are within reasonable bounds of predictions. The amount of skewness depends on the direction of how and is higher for inward flow. Skewnesses are 14.2% at worse and generally better than 5%.