This set is seconded because the inside holes developed some small fissures. It won't cause any ongoing issues and won't impact the quality of coffee.
We recommend a #2 cone filter for this pour-over, and will fit on mugs with 3" rims or less (or up to 3.5" if you want to push it).
Dimensions: approx. 7" h x 5" w
Dishwasher and microwave safe. Note: As with any ceramics, avoid rapid temperature changes (ie: filling an oven-hot vessel with ice water may crack it.)