So the other commenter has all the good deets on the silicone. They don't advertise the raised charger nipple thing, it's just a trait of the 1.5mm jack construction.
As for design, these classic style corded eggs are pretty fantastic, especially for under clothes use. One of the consistent features we found was that they're notably gerthier than you expect from the image, this makes for consistent pressure but can be uncomfortable if you're not used to the size.
Another worthwhile note is g spot vibrators. For those not in the know who may be reading, the g spot is a spongey nerve cluster near the inside of the pelvic bone along the roof of the vagina. While it differs between individuals, the majority of women report lackluster results from g spot vibrations with best results from repeated pulsing squishes. If you know for sure that you're into g spot vibration, go for it, but if you don't know then don't be discouraged if it doesn't feel like it's working. On that note, the girth of the corded eggs can play to the benefit as shiftin the hips and engaging the pelvic floor can stimulate the g spot. My understanding is it takes some practice, but isn't difficult.
I did indeed mean international.