Ring
Tails was working in his new lab, happily experimenting with various chemicals. He sloshed a purple beaker's contents into an Erlenmeyer flask, along with the lavender and gold colored liquids he already had in the flask. Adding colors as he went, he didn't notice that his experiment was solidifying until it hardened into a golden halo just big enough to wear on one's wrist like a bangle, bursting the flask into a dozen glass shards.
A blue blur zoomed into the lab. "You alright?" it asked the startled fox, resolving itself into Tails' new friend Sonic as he spoke.
Tails shook his head dazedly. "Well, yeah, just a few scrapes from the glass..." he replied nervously, "...but I broke the flask."
The hedgehog had stopped paying attention. By the time Tails got his sentence out, he was already inspecting the item. "Wha's this?" he inquired, picking up the golden object and twirling it around his finger.
"I dunno..." Tails picked up the ring from the ground where it had fallen off of Sonic's finger and turned it over in his hands. As he held it still, it sank into his gloves. The fox's eyes widened, but the ring did no harm. On the contrary, it healed all his scrapes. After realizing that the gold item did him no harm, he got up to shut the open door, moving a little faster than he normally would, with a light golden aura, barely visible to all but Sonic's highly trained, quick moving eye, undulating around him.
After a few minutes had passed, spent by Sonic watching his little buddy very carefully, the golden glow around Tails faded, taking with it the faster speed and some of the young fox's energy. As Tails collapsed on the floor, Sonic ran over to pat him on the back. "What're we gonna call it?"
The fox tilted his head. "Whaddya mean?"
"The... thing. It's useful, so what are we gonna call it?"
"I dunno... a Ring?"
The hedgehog shrugged. "Works for me."