Tested in WSF & YellowSFP:
This model has been tested in White Strong Flexible and Yellow Strong Flexible Polished by LilScotty. He reports that WSF fits nice and tight but that the polished colors feel a bit loose due to the polishing process so a thickening treatment may be required if you opt for the colored sets.
These hands have a 5mm attachment post at the wrist to fit into a 5mm port of your choosing. It just so happens that the Kreon combiners and the custom "Super Kreons" that folks are making also use a 5mm port to attach kreon legs that pass for hands to.
These hands have a ball joint at the wrist for expressive hand poses, along with a ball jointed thumb. The fingers can open and close as one and are modeled on the inside to be able to hold a 5mm post.
$if you plan on ordering multiple items of mine, contact me first and I can group them into a single order (by material) to save you a few dollars.$