At least during my ten working trip to the US I was able to invite the three adapters on all available outlets at the airport and hotel without hesitation, quickly and easily my device (smartphone, tablet, camera). None of the plug slipped inside the socket and a power supply had given safe and reliable at all times. The adapters were not hot or have suggested a qualitative weakness in any other point. And yes, they are not suitable for large, round SCHUKO plug - you might as well just take a look at the product photo.
It is worth mentioning, if at all, the fact that the adapter baggy quickly by using a thick power plug, that is possible only should be used with another thick power plug in the following years even as thin plug then slip out the expanded adapter. In practice, not a problem with a piece of tape of the adapter to the "thickness", the other two adapters was the "thinning". Confusion excluded solved problems before the origination.
Conclusion: good travel utensil, low acquisition and in case of loss not a big slap in the financial office. Absolute buy recommendation.
