ProtonMail, the encrypted email service that has previously touted itself as “NSA-proof,” has made a limited number of lifetime subscriptions available to mark Black Friday and Cyber Monday.

Founded out of CERN in 2013, Geneva-based ProtonMail launched in beta in 2014 and went on to raise more than $2.5 million in funding ahead of its proper launch earlier this year. ProtonMail’s key promise is to provide a secure email service that uses client-side encryption so all data is encrypted before it arrives on the company’s servers.

Though ProtonMail does offer a free tier, it comes with restrictions, and those wishing to upgrade to ProtonMail Plus (€5.00 / month or €48.00 / year) or ProtonMail Visionary (€30.00 / month or € 288.00 / year) can gain access to more storage, custom domains, unlimited messages, and more. Back in 2014, the Swiss company made just 150 “Lifetime” accounts available as part of a crowdfunding campaign to help its early growth. They cost $997 at the time, and those were the only such accounts ever made available. “Without this critical support and trust from these early backers, ProtonMail would not have come into being,” the company said in a statement

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Lifetime accounts give all the benefits of a Visionary subscription, except that you don’t have to pay for a subscription. For now, only 50 more accounts are being made available for a one-off payment of €1337 ($1,400), so one should pay for itself after about six years. However, there are a handful of other perks that may make the offer more appealing in the short-term — Lifetime accounts offer automatic access to any future services ProtonMail may launch, plus the company actually allows people to resell them on secondary markets — as Lifetime status to be transferred to any other ProtonMail account.

A mere 50 accounts isn’t much, of course, and given that online privacy is emerging as a key concern for millions of people, these will likely sell out when they go on sale today through Monday. Encryption and other privacy tools are growing in popularity, and Donald Trump’s election victory a couple of weeks back triggered a spike in popularity — ProtonMail announced that signups had doubled, while other private messaging and VPN services also reported an increase in downloads.

So can we expect to see any more Lifetime accounts made available in the future? Maybe, maybe not. “In the unlikely event that we make Lifetime Accounts available again in the future, they will be certainly more expensive,” the company confirmed.

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