I HAVE 18 1/2" CATV FITTINGS, THEY ARE BULKHEAD TYPE. AN 'N' CONNECTOR CAN BE SCREWED RIGH ON. I CAN SUPPLY 'N' CONNECTORS ALSO. ASKING $2.50 EACH OR $5.00 FOR ALL. ADD SHIPPING. R. A. BOB TAYLOR W5LBT ANTENNA TRACKING SYSTEMS http://www.qsl.net/w5lbt GAS ENGINE POLUTION SOLUTIONS http://www.teccontrols.com 225.272.4303 225.241.7852