The kind folks at Liquid Planet sent me two packages of coffee and a French press travel mug by Planetary Design. These mugs are stainless steel with an enamel coating (in many colors) and fit into the usual car mug holders, making them 
handy for commuters. It comes with two lids — a regular lid and the lid with the plunger for using it as a press. The regular lid has a sliding cover for the sipping hole which snaps open and stays in place.
The mug holds 14 oz. Depending upon your preference of using 1 tablespoon of ground coffee per 4 oz of water, or 2 tablespoons per 6 oz, you’ll want to use about 3.5 to 4.25 tablespoons of coffee per mug. The instructions with the press recommend 2 to 4 tablespoons. They also say to add cream or sugar if desired to the grinds, before adding the water. This seems icky to me, but I have read reviews where people said it worked okay. As a black coffee drinker, I did not experiment.
The plunger has a good, fine screen. The margins of the plunger are springy plastic which have enough give to slide freely but also provide a snug fit. The plunger depresses straight and smoothly and the button on the handle goes flush to the lid.
You can, if desired, drink directly from the mug with the plunger lid in place. The sipping hole is also equipped with the same fine screening as the plunger, a nice touch that acts as an additional filter. Coffee also pours drip-free from this hole if you want to pour into a cup.
Prior to trying this mug, I would never have recommended drinking directly from the mug with the grounds still in the bottom. Surely it would be overextracted and bitter. The Planetary Design web site says this does not occur with their design…
“When the grounds are pressed to the bottom (picture a hockey puck), the overall surface area, (all the little points of contact) decreases thousands of times over, leaving the water very little surface area with which to continue infusion.”
I gave this a try. I steeped four minutes, pressed the coffee — then had to step away from my desk for 45 minutes. When I returned, the coffee was a perfect drinking temperature, and smooth without bitterness, down to nearly to the end of the cup. I poured out the last half-ounce to see how much sediment came out, and it was much less than with a regular French press.
Another feature is that the bottom of the mug is removable, revealing a little canister with a twist-off lid. The mug bottom even has small rubber nibs that center the canister and hold it safely in place — another nice touch. The canister holds 4 tablespoons of coffee. While this is advertised as being enough to brew two extra mugs, I think 2 tablespoons per mug is too stingy.
I’m of the opinion that most of the stainless steel mugs I’ve tried change the taste of the coffee. I have to say that I did not find this to be the case with the Planetary Design mug, which is made from “restaurant-grade” stainless. Is this different from the materials in a typical Nissan mug? It looks shinier, so maybe so.
This mug is a nifty design that is well engineered and constructed, and shows great attention to functionality in the details. It is top-rack dishwater safe, and replacement parts are available. I can understand why it had good reviews (e.g., 100 Cups of Coffee). The only bummer is that it is made in China. It’s now made in the U.S.
Liquid Planet has a sustainable business philosophy, which further helps me recommend their products (disclaimer: I have no financial or other beneficiary interest in these companies). This includes a program called Farmers First, a Fair Trade alternative that has a sustainable environment provision. This provision notes verification by an independent auditing firm.
I was impressed with this product, and if you are interested in a portable thermal press pot, certainly give this one a try.
Revised on December 21, 2020
