Tea infusing spoon
These are easy to fill – you can kind of shovel the loose tea into the infuser, like a digger, and then snap them shut. Then they feel like a teaspoon in your hand as you get your brew going. They do have a nice action.
(There are other sprung types which you have to keep squeezing open while you fill them with tea – a real faff.)
Sturdy stainless steel.