ContigoWest Loop Travel Mug Tea Infuser Accessory, Greyed Jade

Can the infuser stay in the mug while drinking? Or does it HAVE to be removed before tea consumption?

can this be used with the autoseal lids on the older mugs before they were called 'west loop' ? My lid looks the same but the mug is a few years old.

how many tablespoons of tea fit in this? is it large enough to hold enough tea leaves (taste/potency-wise) for the 24oz contigo travel mug?

What material is the drip cup made of? Is it safe to drink from, if I wanted to use it as a cup?