These Gamakatsu Tetron Tanago Microfishing Hooks from Japan are snelled although they are snelled to thread rather than mono. The snells are about 1.25" (3 cm) long and end in a loop for easier attachment to your line or tippet. These are specifically made for microfishing.
They come in slightly different hook shapes for specialist application. All will work well when microfishing for tiny fish.