---
product_id: 653538830
title: "OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black"
brand: "dupota"
price: "€ 39.04"
currency: EUR
in_stock: true
reviews_count: 9
category: "Dupota"
url: https://www.desertcart.be/products/653538830-oa-991ex-plus-scientific-calculator-552-functions-2-line-10
store_origin: BE
region: Belgium
---

# Multi-line natural display 552 functions Dual solar & battery power OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black

**Brand:** dupota
**Price:** € 39.04
**Availability:** ✅ In Stock

## Summary

> 🔬 Elevate your calculations — because precision is the new power move.

## Quick Answers

- **What is this?** OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black by dupota
- **How much does it cost?** € 39.04 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.be](https://www.desertcart.be/products/653538830-oa-991ex-plus-scientific-calculator-552-functions-2-line-10)

## Best For

- dupota enthusiasts

## Why This Product

- Trusted dupota brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Built to Endure:** Dual power system with solar + button battery and durable sliding cover ensures nonstop performance.
- • **Speed Meets Precision:** Quad-core processor accelerates matrix and vector operations, saving you valuable time.
- • **See Every Step Clearly:** High-resolution 2-line display shows formulas and results simultaneously for intuitive learning.
- • **Lightweight & User-Friendly:** At just 125g with anti-slip keys and quick fraction-decimal toggle, it’s made for on-the-go pros.
- • **Master Complex Calculations:** 552 advanced functions from algebra to integration empower your toughest problem-solving.

## Overview

The OA-991EX Plus is a professional-grade scientific calculator featuring 552 functions including spreadsheet, matrix, and statistical calculations. It boasts a high-resolution 2-line natural display for clear formula visualization, powered by a dual solar and battery system for long-lasting use. Lightweight and durable, it’s designed for middle to high school students and teachers who demand speed, accuracy, and portability in their daily calculations.

## Description

desertcart.com : DUPOTA OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black : Office Products

Review: Amizon - My niece needed this for college and loved it
Review: Increible

## Features

- 【552 Calculation Functions】Scientific calculators 991ex features 552 functions, including spreadsheet, exponential, matrix calculation, statistics, integration, algebra, complex number calculation, standard deviation, and more, suitable for handling complex equations and statistical data. From beginner to advanced courses, its practicality can meet the needs of various digital fields.
- 【High Resolution & Multi-line Display】991ex scientific calculator is equipped with a high-resolution multi-line display that supports natural display of mathematical formulas and fractions, presenting expressions intuitively and showing the calculation process and results simultaneously. Adjust the screen contrast according to your preference for a clear and comfortable experience.
- 【High-Efficiency Calculator】Scientific calculators has an integrated spreadsheet mode that supports data input and formula calculation; advanced operations such as 4×4 matrix and vector operations, with a quad-core processor to enhance calculation speed, making it faster to solve high-order equations and perform matrix operations, meeting the needs of efficient calculation.
- 【Long Battery Life & Durable】Fraction calculator has a dual power system of solar and button battery for long-lasting operation. It automatically shuts down after 8 minutes of inactivity. Sliding back cover protects the calculator body, making it pressure-resistant and durable, meeting the needs of high-intensity study and outdoor use, providing peace of mind in exam scenarios.
- 【Ultra-light & Portable】Advanced scientific calculators is designed to be lightweight (about 125g), suitable for carrying around. The button layout is clear, and the anti-slip material enhances the operation feel. It has various function keys to simplify complex calculations, including a "CHG" button for switching between fractions and decimals, making precise value calculations easy.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0D9Q6RK43 |
| Best Sellers Rank | #223,325 in Office Products ( See Top 100 in Office Products ) #132 in Scientific Calculators |
| Brand | DUPOTA |
| Calculator Type | Engineering/Scientific |
| Color | black |
| Customer Reviews | 4.3 4.3 out of 5 stars (67) |
| Display Type | LCD |
| Enclosure Material | Plastic |
| Item Dimensions L x W | 6.5"L x 3.15"W |
| Item Weight | 125 Grams |
| Manufacturer | DUPOTA CO.,LTD. |
| Mfr Part Number | OA-991EX PLUS-XY |
| Model Name | OA-991EX PLUS |
| Model Number | OA-991EX PLUS |
| Number of Batteries | 1 LR44 batteries required. (included) |
| Power Source | Solar Powered |
| Screen Size | 2.5 Inches |
| UPC | 726434206879 |

## Product Details

- **Brand:** DUPOTA
- **Calculator Type:** Engineering/Scientific
- **Color:** black
- **Power Source:** Solar Powered
- **Screen Size:** 2.5 Inches

## Images

![OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black - Image 1](https://m.media-amazon.com/images/I/71edBbg+O4L.jpg)

## Available Options

This product comes in different **Size** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Amizon
*by M***W on September 11, 2025*

My niece needed this for college and loved it

### ⭐⭐⭐⭐⭐ Review
*by D***A on October 8, 2025*

Increible

### ⭐⭐⭐⭐ Terrible Design - Terrific Function
*by N***N on August 12, 2025*

With 550 functions this calculator would be a fine choice for students from middle school to college and into professional work. Keys work well. No missed presses. The included slide on cover protects the keys while not in use or being carried in a backpack . Solar and battery power is a definite plus. Major downside: The faceplate is embossed! This was obviously designed by an "Artsy" person rather than an actual user since the embossing makes it difficult to impossible to read the alternate key symbols in almost any lighting situation. Had to return it! Very disappointed as I really liked it otherwise.

## Frequently Bought Together

- DUPOTA OA-991EX Plus Scientific Calculator 552 Functions 2-Line 10+2 Digits Written Display Solar Battery - Ideal for Middle High School Students and Teachers, Black
- Desk Calculator 12 Digit Extra Large LCD Display, Touch Comfortable with Big Buttons, PXY Two Way Power Battery and Solar Standard Function Office Calculators
- Desktop Calculator Extra Large 5in LCD Display 12-Digit Big Button Giant Accounting Calculator, Battery & Solar Powered, for Office Business & Home(OS-6815)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.be/products/653538830-oa-991ex-plus-scientific-calculator-552-functions-2-line-10](https://www.desertcart.be/products/653538830-oa-991ex-plus-scientific-calculator-552-functions-2-line-10)

---

*Product available on Desertcart Belgium*
*Store origin: BE*
*Last updated: 2026-04-22*