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OA-991ES Plus Scientific Calculator 417 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers

  • Based on 54 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Saturday, Aug 30
Order within 13 hours and 12 minutes
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Size: 991ES PLUS


Features

  • 417 Computing FunctionsThe scientific calculator with 417 functions for Include exponents, matrix calculations, statistics, integral, algebra, complex number calculations, standard deviation,etc.Apply to school, office or business, and more. Its practicability could meet the needs of various digital fields, and ideal for students.
  • 2-line Display CalculatorFeaturing a 12-digit large display, this calculator scientific shows input and results together, minimizing errors. Ideal for offices and teaching, it offers clear formula display for precise math calculations.
  • Dual Power Supply DesignThe scientific calculator is equipped with solar panels and replaceable button batteries, dual safe uninterruptible power supplies, and has an automatic power-off function. It will automatically shut down after 8 minutes of non-use, which has the advantage of energy saving.
  • Ultra-light and PortableThe scientific calculater body design is thin, ergonomic and comfortable to hold. Comes with a slide-on hard case to protect the buttons and body of the device. It's an excellent student teacher supplies. Weight: 125g; Dimensions: 165x 80 x 15mm.
  • More Sensitive KeyThe scientific calculate buttons are made of high-quality ABS plastic material, elastically fit the buttons, and the buttons feel comfortable.

Brand: DUPOTA


Color: black


Calculator Type: Engineering/Scientific


Power Source: Solar Powered


Screen Size: 2.5 Inches


Product Dimensions: 6.5 x 3.15 x 0.1 inches


Item Weight: 4.4 ounces


Item model number: OA-991ES Plus


Batteries: 1 LR44 batteries required. (included)


Date First Available: July 31, 2024


Manufacturer: DUPOTA CO.,LTD.


Country of Origin: China


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Aug 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Nice scientific calculator
Size: 991EX PLUS
I am quite pleased with this calculator. It comes programed with multiple functions, in some cases going beyond a typical scientific calculator. Vector, matrix, probability, integral, or statistical calculations, this calculator can handle surprisingly many of them. As a primary user of TI calculators, I found transitioning to the Dupota calculator a bit challenging due to the learning curve. As long as the protective buyer is okay with that, this solar calculator is extremely powerful and a great choice. ... show more
Reviewed in the United States on December 29, 2024 by RTMPX

  • My daughter used this in college
Size: 991ES PLUS
It got the job done!
Reviewed in the United States on December 21, 2024 by JG

  • Convenient
Size: 991EX PLUS
This calculator has been a great tool for school! The 552 functions cover everything I need, and the two-line display makes it easy to track my calculations. It’s reliable, and the solar battery is a huge plus for not having to worry about changing batteries.
Reviewed in the United States on December 22, 2024 by Arman

  • Going strong
Size: 991ES PLUS
Had to get a non-graphing for a university course. This one fits the bill, sustains small drops, and is pretty comfortable to hold.
Reviewed in the United States on December 10, 2024 by Xoxo

  • Useful and great price
Size: 991EX PLUS
This calculator is a useful tool for simple math. The solar and battery operation is reliable, and the display is clear and easy to read. It’s lightweight yet durable. It's easy to navigate all the functions, but this calculator gives some answers in fraction form. Sometimes this wasn’t a problem for me, but it was inconvenient on tests. I couldn't figure out which function converts the fraction to a decimal or if it had a function like that at all. ... show more
Reviewed in the United States on December 18, 2024 by Rebekah

  • Great Calculator for School and Study
Size: 991EX PLUS
The OA-991EX Plus Scientific Calculator is an excellent choice for both students and instructors. It includes 552 functions and can readily handle everything from elementary algebra to more complex computations. The two-line display includes both the issue and the answer, making it simple to follow along. With solar and battery power, you won't have to worry about running out. This calculator is reliable, simple to use, and ideal for students! ... show more
Reviewed in the United States on November 4, 2024 by Shiva

  • Does what we need it to and appearently a thousand other things.
Size: 991ES PLUS
I got this for my kid to have a calculator that she can take back and forth to school without having to worry so much if it gets damaged or lost. We have another brand name calculator that she leaves at the house, and this one seems to do everything that the more expensive one does. Granted we will probably never need or use 95% of the features. It seems reasonably well made with no issues going back and forth thrown in a backpack. ... show more
Reviewed in the United States on October 27, 2024 by 2L student

  • great calculator
Size: 991EX PLUS
I have 2 kids that are taking Algebra 2. I debated purchasing the pricey graphing calculator, however, I hesitated. They use an online graphing calculator currently and did not seem motivated to switch. When I was in school, the physical graphing calculator was the way to go, so I asked the guidance counselor for input. They stated that students choose what they prefer, and that it is 50/50 on preference. Mine seem to prefer the online version. With testing in the future, I wanted them to have a scientific calculator, as I feel that this would be what is needed most often (not as much needed with graphing), and it would be quicker than accessing the online one. They agreed and have been using this one to get used to it. There are so many features, so it will take time to learn them and I do not think we will ever need them all, but they are good to have. It is a bit overwhelming, so it is fantastic that they include an instruction book. It is extremely lightweight, which is good. However, it does not feel as sturdy as ones that I have used in the past. So a pro to that is less weight, con is possibly less durable. It does have the sliding protective case, so hopefully that will help. I like that it functions with solar power, so less battery replacements. Overall, we are very pleased with this. It rivals the other brands that we have used and is very reasonable in price. With kids having the option of online graphing calculators in school and for testing, they are not as necessary as they were in the past. The need may change in the future for college courses, but so far so good. ... show more
Reviewed in the United States on September 9, 2024 by Ren10

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