Transmission cooler rubber hose size

Looks like I have a small leak on the rubber portion of my trans cooler hose. Thought it might be residual after some work, but I’ve cleaned it up a few times and it keeps coming back. I’m assuming what I have is not OEM as there is a smaller hose that connects to both the radiator and the metal portion down below, but there’s a slightly bigger rubber hose they both feed into which doesn’t really make sense (see pictures). Would one hose the same size from radiator to metal line fix it? Seems too easy almost. And if so, is this the correct size rubber line? This line came up after I googled the writing on the hose currently connected on the bottom in yellow. The other picture is from Rock auto. Thanks

 

It looks like O.E. hose from the markings and foam sleeving.