Toronto-based Rakuten Kobo Inc. revealed its new mid-range e-reader, the upgraded Kobo Aura H20, on Tuesday.

In updating the model that was first introduced to the market in August 2014, Kobo CEO Michael Tamblyn says the firm applied lessons that it learned in developing its flagship Kobo Aura One e-reader. That flagship model debuted last year, offering a large screen-size, waterproofing, and a bevy of connected services. Even to Tamblyn’s surprise, the premium hardware priced at $249.99 is overperforming.

“We’ve been very pleasantly surprised with how the premium e-reader market has been developing,” he says.

At first, Kobo bet its premium hardware would be niche, taking about five per cent of the market. Most e-reader makers aim to produce hardware that is as low cost as possible, so Kobo reasoned its pocket-sized Aura e-reader would capture the lion’s share of its sales. But models like the Aura H20 proved that wrong, accounting for about 25 per cent of the sales, and the Aura One has even more incremental sales, Tamblyn says.

“The great thing about books is that they are shockingly durable as a medium,” he says. “We’re fighting with Netflix, we’re fighting with Facebook, we’re fighting with any other service that could get that spare hour of your day.”

Part of winning that fight, in Tamblyn’s view, is to help avid readers feed their inner bookworm near water. Kobo’s research shows that about half of its “heavy readers” demographic spend time reading in a situation that risks a soaking. From in the bath to on the dock, trusting your device isn’t going to get wet is one less stress.

With the new Aura H20, Kobo is introducing a feature it calls HZO protection. It’s a nano-coating layer that waterproofs the device to IPX8 standards without the need for seals on the ports, like those seen on the original Aura H20. The new device is waterproof for 60 minutes submerged at a depth of two meters.

Aside from the certification testing, Tamblyn says Kobo staff run their own real-world tests on the hardware.

“How is it when you spill water on it? What about coffee?” he says. “The great thing is you can wash it off and just start reading again.”

Another new feature on the Aura H20 is the ComfortLight Pro. First introduced with the Aura One, this changes the frequency of the backlight to be more in line with circadian rhythm. So it’s blue light during the day, shifting to a more red spectrum as it gets closer to night. Kobo says that helps avoid sleep disruption if you’re up late reading in bed.

“We had users that were very concerned with having technology with them before bed and the idea that the blue light they emit would disrupt their sleep patterns,” he says. “So by the end of the day you’re getting light out of your e-reader that’s more like candlelight, or light from a sunset.”

Just like music enthusiasts are happy to purchase a premium pair of headphones, Tamblyn says book lovers will purchase a premium e-reader. He says Kobo has an advantage as the largest standalone e-reading service in the world, with a business model not bogged down by other activities.

“We’re continuing to get better on how to be the best bookseller possible,” he says.

The new Kobo Aura H20 is available for pre-order May 15 and will be for sale at $199.99 on Kobo.com and at select retailers May 22. It features 8 GB of storage (enough for 6,000 e-books), a 6.8″ e-ink touchscreen, and a battery that lasts long enough for weeks of reading.