Is the Toshiba OWCES2.5BPU2S still current for ...

I found this in an estate I cleared out, erased it, and am wondering if I can still use it with El Cap?

The OWCES2.5BPU2S name seems to belong to an external hard drive enclosure form macsales.com. Assuming the Toshiba part refers to the hard drive inside it, there should no no reason you couldn't use this with el Capitan.

As long as its formatted in a way el Capitan can use, i.e HFS+, FAT32 etc... you should be able to just plug it in.