you can buy a chatillon hanging scale from www.itinscales.com the one i have is the 0-60 lb. in-60 and it cost about 145.00. after you purchase the scale, you have to send it to the international gamefish association to be certified. the cert. is good for one year. i have mine for coho and steelhead. for a big king you would have to get a 0-150 pound scale. for a record to be official, you can't weigh a fish on a boat. you have to be standing on the shore or in the water.