i havent installed them yet. the US car tool ones are also 1/8" thick too. they are open at the top, but box to the floor all the way down making a super clean install. i dont think they go as far back as mine do on the rear rails, but are nice if you dont want to slot the floor. according to my dial bathroom scale they weigh 14 lbs each, and 14.8 lbs each on my digital bathroom scale. of course these are not calibrated like a Drs office. so im not sure how far off they are. I think they are one pound off to the light side.
either way you go i recommend running your parking brake cable inside the framerail like i did. otherwise with the US car tool you will have to cut a long slotted hole for the cable to come out otherwise it may rub on the connector.
i payed $25 for the material, and have a lot of time making them fit as nicely as they do, or you can spent $170 plus on the US car tool ones and have a clean easier to install setup as well. i have more time than funds so i went this route. figured i could spend the remainder of the cash elsewhere.