Thanks...I almost I have enough to finalize my order. Please fill in the blanks: Filter BW Shape Factor 200 250 370 2.1 400 435 2.1 500 1000 1063 1.6 1800 2700 2800 2888 1.6 *All data taken from 8-pole plots...nothing available for 5-poles filters or the 1.8 8-pole. 73, Bill W4ZV