This is the OEM spool from the 2016 Daiwa Zillion SV TW reel. It offers a nice performance upgrade to some of the more heavily braked SV spools, and offers more control over some of the Mag V and Mag Z spools. It is a 34mm diameter spool. It fits the following models with no modifications:

Daiwa TDZ, Steez, Steez EX, Steez SV, Steez SV TW, Steez A, SV103, Zillion SV TW,

Zillion SV TW G, Megabass IS,

Daiwa Z02-2423