The plugs with a mini S4 should be used. All 3 purchased from me sets were tested on it.
The plug for the headphones fit properly, is secure enough and is only minimally, so that you can pull it out with your fingernails again.
But the plug for the micro-USB connector does not fit. He sits so loosely that it already falls out again by light touch. The desired protection in this case it can not be guaranteed; but it certainly the loss of the plug.
Conclusion: If you want to protect only the headphone jack can not go wrong here. But should refrain from purchasing who would also protect the Micro-USB connector.
Addendum: After I informed the seller about the non-matching plugs were impeccably refund me the purchase price and shipping costs. This testifies to a fair seller. Power but unfortunately the article no better. About-fit replacement I would have liked more.