Empire of the Sum: The Rise and Reign of the Pocket Calculator

Empire of the Sum: The Rise and Reign of the Pocket Calculator

Marsoni

M251S

$32.50

Get it in 3 business days with 1 day shipping. Friday, May 29

Empire of the Sum: The Rise and Reign of the Pocket CalculatorThe hidden history of the pocket calculator a device that ushered in modern mathematics, helped build the atomic bomb, and went with us to the moon and the mathematicians, designers, and inventors who brought it to life.

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This Offroam phone mount is not the cheapest option, but it is easily the most functional and sturdy one available, especially for second-generation Toyota Tacomas. I went through several plastic phone mounts before this and should have bought this one from the start to save both money and frustration. Installation was very simple, and it is even easier to use day to day. I like that this mount uses adjustable arms to grip the phone rather than relying on MagSafe. It keeps my phone secure even on rough terrain and offers plenty of flexibility for positioning the phone exactly where you want it.

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Reviewed in the United States on January 25, 2026

Verified Purchase

Jason Lefebvre

Lowell, US

★★★★★ 5

Top notch mount with high build quality

I love it when I take a chance and spend some extra money hoping for a quality product - and it actually pans out. I bought this for my 2nd gen Toyota Tacoma (2014). The install was fast. Instructions were clear. The mount is ROCK solid and has two points of articulation so I can position my phone well. I couldn't ask for a better product. The price I paid was a little steep for a mount, but if you demand quality then look no further.

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Reviewed in the United States on October 21, 2025

Verified Purchase

Michael

Pawtucket, US

★★★★★ 5

Must buy.

use this thing every day I combined it with a quad lock MagSafe compatible charger and I could not imagine my life without it makes charging and using Google maps so much easier. really easy install extremely sturdy and it fit perfectly.

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Reviewed in the United States on January 6, 2026

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Amazon Customer

Carnegie, US

★★★★★ 1

Not compatible for Kia K5

Unfortunately, I had to return due to not being capatible with my K5.

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Reviewed in the United States on September 10, 2025

Verified Purchase

Amazon Customer