December Dripper

The December Dripper is a flat-bottomed, stainless steel pour-over dripper with adjustable flow. It was designed by Nick Cho of Wrecking Ball Coffee Roasters and the Korean barista Youngmin Lee, and it went on sale in South Korea in February 2017. It looks a lot like a Kalita Wave and takes the same filters, but its base has 12 holes that you open or close four at a time by turning the dripper. Here’s what each setting does, recipes to start with and where it came from.

The short version

• A Kalita-style flat-bottomed dripper that takes Kalita Wave filters.
• Four settings: 0 is closed, 1, 2 and 3 open 4, 8 and all 12 holes.
• Setting 0 holds the water in, so you can bloom or steep before it drains.
• Prima Coffee’s single-cup recipe: 15 g of medium-coarse coffee to 255 g of water (1:17), finishing in 3 to 4 minutes.
• The big idea: change the flow, not the grind, when you brew more or less coffee.

What makes the December Dripper different?

Most drippers have one flow rate, built into the size and number of their holes. With those, the only ways to speed up or slow down a brew are to change the grind, the dose or how you pour.

The December gives you a fourth control. Its upper part turns on a screw thread that fixes it to the base, and as it turns it seals the holes four at a time. Daily Coffee News describes the positions as fully closed, then four, eight or 12 holes open, with marks on the outside so you can change setting mid-brew.

Nick Cho explained the thinking to Sprudge. For pour-over, he said, the target brew time sits somewhere between 3 and 4 minutes, and there’s an ideal grind for that time. The trouble is that when people brew a bigger or smaller batch, they often move the grind away from that ideal to hit the time. The December lets you keep the grind and change the flow instead.

Because setting 0 shuts the dripper completely, it also works as a valve dripper: you can bloom or fully steep the coffee, then open it to drain. Daily Coffee News called it the only adjustable-flow immersion dripper to use Kalita filters, with their flat, round bottom and fluted walls. For how it fits among other valve brewers, see the valve immersion dripper guide.

Which setting should I use?

Pick the setting by how much coffee you’re making. The guidance below is the maker’s, as quoted by the Coffeehouse Blunders review, alongside Prima Coffee’s summary:

Setting	Holes open	Maker’s guide (via Coffeehouse Blunders)	Prima Coffee
0	None	Closed, for the bloom	Closed
1	4	About 300–360 ml	Low flow, single cups
2	8	About 400–475 ml	Medium flow, 1–2 cups
3	12	About 500–700 ml	High flow, batches up to 1 litre

The range is wide. Michael Butterworth, testing it against the Kalita Wave, Gino and Blue Bottle drippers for Prima Coffee, found that on its slowest setting the December was slower than any of them, and on its fastest setting faster. Prima measured setting 3 draining about 30% faster than a 185-size steel Kalita Wave.

How much coffee and water should I use?

Prima Coffee published four December recipes in 2017. They all bloom on setting 0, then open the dripper:

Recipe	Coffee	Water	Bloom (setting 0)	Then	Total time
Single cup	15 g	255 g (1:17)	45 g for 30 sec	Setting 1, 2–3 pours	3:00–4:00
Large batch	40 g	680 g (1:17)	120 g for 45 sec	Setting 1 for 250 g, then setting 3 with pulse pours	3:30–4:00
Medium variant	30 g	500 g (1:16.7)	100 g for 60 sec	Setting 2: 150 g, 150 g, then 100 g	4:30–5:00
Iced	40 g	455 g, plus 225 g of ice	120 g for 30 sec	Setting 1 or 2, 300 g in 3 pours, stir, then 135 g	3:00–4:00

Prima says it usually brews with the kettle at 200–210°F (93–99°C). It also says the slow settings make doses as small as 10 g possible with a 3 to 4 minute brew, and suggests trying setting 2 for doses of around 25 g.

What grind size should I use?

Coarser than you might expect. That’s the point of the dripper: because you can slow the flow, a small dose doesn’t need a fine grind to reach a 3 to 4 minute brew. Prima suggests:

• Single cup and medium variant: medium-coarse, between table salt and kosher salt.
• Iced: around kosher salt.
• Large batch: a bit coarser, like coarse salt, and slightly coarser than you’d use for a similar brew in a Kalita Wave.

Prima’s reasoning is that coarser grinds produce fewer fines, and that a longer brew time tends to taste sweeter. With a small dose on a normal dripper, you’d usually have to grind finer to stretch the brew time; on the December you turn it to setting 1.

How do you brew with a December Dripper, step by step?

This is Prima Coffee’s single-cup recipe:

1. Put a Kalita Wave filter in, turn the dripper to 0 and add 15 g of medium-coarse coffee.
2. Bloom: pour 45 g of water at 93–99°C and wait 30 seconds.
3. Turn to setting 1.
4. Pour the rest in two or three slow, circular pours to 255 g. Start each pour when the water drops to about 1 cm (Prima says half an inch) above the coffee, and don’t let the bed run dry.
5. Let it drain. It should finish at 3 to 4 minutes.

Brew mode on this page times the bloom for you. If it runs long, grind a little coarser or try setting 2; if it runs short or tastes sour, grind a little finer.

What goes wrong, and how do I fix it?

Problem	Likely cause	Fix
Water leaks out of the side on setting 0	Too much water held in the closed dripper	Coffeehouse Blunders found that turning to setting 1 or higher stops it
Brew runs well past 4 minutes	Setting too slow for the dose, or grind too fine	Turn up a setting, or grind a little coarser
Finishes too fast and tastes thin or sour	Setting too fast for the dose, or grind too coarse	Turn down a setting, or grind a little finer
Hard to pick up after brewing	Steel gets hot and there’s no handle	Lift it by the silicone sleeve at the top

What are the downsides?

• It gets hot. Butterworth found the steel dripper very hot to handle after brewing, and thought the handle-free design less than practical. Later reviews mention a silicone sleeve at the top to protect your hand.
• It costs more than most flat-bottomed drippers, Butterworth noted.
• It takes some working out. Prima says the flow control makes it “a little tricky to figure out the right parameters” at first, which is why it published its recipes.

What is it made of?

Cho told Sprudge it’s 18-10 stainless steel with a PTFE gasket (PTFE is the material best known as Teflon). He chose steel because, in his experience with the Kalita Wave, the stainless steel version had been the most popular: less fragile than ceramic or glass, and it soaks up less heat than ceramic. The launch price in Korea was 44,000 won, about $38 at the time, according to Daily Coffee News, and Kickstarter pre-orders started at $40.

Who made the December Dripper?

The December was designed by Nick Cho, co-founder of Wrecking Ball Coffee Roasters in San Francisco, and Youngmin Lee, a Korean barista and CEO of CBSC International Coffee Lab in Seoul. Sprudge credits Cho with helping to create the Brewers Cup competition and popularising the Kalita Wave in the United States, and Daily Coffee News notes that Wrecking Ball owns Kalita USA, which explains the Kalita connection.

Cho told Sprudge that he and Lee had been friends for more than ten years, and that Lee had offered to get his product ideas made in Korea. It took almost three years from the first sketches to the first production units, with about six prototypes and more than 20 sketches along the way.

• February 2017: the first-generation December went on sale in South Korea through CBSC International Coffee Lab. Cho later described it as “more of a public beta test”.
• 11 April 2017: a Kickstarter launched to fund final development and US production. Butterworth reported in June that it had smashed its funding goal.
• 2021: owners on the Home-Barista forum said it had become hard to find, with Wrecking Ball selling it for $55 when in stock.

Check current retailers before you buy, as availability has been patchy.

How do you clean it?

Throw away the filter and grounds, then rinse the dripper under running water, turning it through its settings so nothing stays trapped around the holes.

General guidance only. Take care with hot water and hot steel, and follow the maker’s instructions for your dripper.

December Dripper vs other methods

• Kalita Wave: the flat-bottomed dripper the December is based on, with three fixed holes.
• Valve immersion dripper: how the December compares with other drippers that can hold water in.
• NextLevel Pulsar: a later flat-bottomed dripper with a flow valve and no bypass.
• Hario Switch: a V60 cone with an on-off valve.
• Clever Dripper: steep, then drain on a mug.
• V60: the classic cone pour-over, with one big hole.

Explore every hybrid brewer in the hybrid chapter.