Transmission cooling line fitting size help

the cooler kits all seem to come with those fittings. if you want i'll see if i have any and send them to you. i never use them. i've done steel braided rubber hose w/ barbed fittings to fill the gap between the stock lines and rad. sucks, almost always seeps. steel braided rubber from the trans to rad w/ AN fittings on both sides. works well, watch the routing. PTFE w/ AN fittings from the trans to the rad. better than rubber hose. and hard lined the whole thing using the stock lines. cut the ends near the rad and use the proper hard line compression fittings and bend up what you need. looks the best but your going to make some bad bends when you're learning. all of these were for installing a cooler.