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The Calculated Industries 4050 Construction Master 5 is a professional-grade calculator designed for contractors, estimators, builders, and carpenters. It supports both metric and imperial units, offers specialized functions for complex construction math including stair layouts and rafter calculations, and helps reduce material waste with precise volume and area estimations. Powered by two long-life LR44 batteries and protected by a durable slide cover, it’s a reliable tool that streamlines on-site and office workflows, backed by a one-year limited warranty.










| ASIN | B0008GO6A6 |
| Batteries | 2 LR44 batteries required. (included) |
| Batteries Required? | Yes |
| Batteries included? | Yes |
| Battery Cell Type | Lithium Manganese Dioxide |
| Best Sellers Rank | 153,490 in Stationery & Office Supplies ( See Top 100 in Stationery & Office Supplies ) 63 in Financial & Business Calculators |
| Colour | Black |
| Customer Reviews | 4.5 4.5 out of 5 stars (216) |
| Date First Available | 12 Mar. 2007 |
| Delivery information | We cannot deliver certain products outside mainland UK ( Details ). We will only be able to confirm if this product can be delivered to your chosen address when you enter your delivery address at checkout. |
| Display style | LCD |
| Item Package Quantity | 1 |
| Item Weight | 170 g |
| Item model number | 4050 |
| Manufacturer | Calculated Industries |
| Material | Plastic |
| Part Number | 4050 |
| Power Source | Battery Powered |
| Product Dimensions | 15.24 x 7.62 x 2.54 cm; 170 g |
A**R
makes marking out a breeze
a great piece of kit for anyone to have. makes marking out and finding quantities and volumes a doddle
P**6
Brilliant tool
Great tool for construction, I’ll be using this to build my staircase, used it for a few jobs already, it’s great.
G**.
Best thing ever, in the history of ever ness!
I love this construction masker calculator! I purchase a lot through amazon, this is, with out question my best purchase to date! There are tons of great videos out there to show you how to use, and how to customise! The main reason I like this particular model, is down to the fact I can use it in Metric. Being in the uk we use both matrix and imperial, this is so versatile I can use it interchangeably. A must have!!!!
N**7
helpful gadget.
Bought for husband to use at work. Arrived well packaged & in the allocated time. He has used this a few times already & is very pleased with it.
N**.
Very handy
Great piece of kit for any carpenter/joiner. Great for working out roof rafters and stairs. Highly recommended.
D**Z
Fantastic calculator, saves time doing calculations on site.
Great price. Does what it says on the tin. Fits into pocket.
A**N
Easy to use
Fantastic bit of kit, Highly recommended.
D**E
Great product
Takes all the hard work out of measuring and working out for materials
W**Z
Jag gillar allt
M**.
Purchased the Calculated Industries 4050 Construction Master 5 for my son, a second-year architectural engineering student, and according to him, it's been a game-changer. Here's why it's become such an essential tool: Complex Calculations Simplified: This calculator simplifies complex construction math, crucial for his demanding courses. It's making tough calculations quicker and more accurate, saving him time and stress. Designed for Engineering Tasks: Tailored for architectural and engineering calculations, it offers functions that are directly applicable to his studies and future profession, enhancing his learning and project work. User-Friendly: Despite its advanced capabilities, the Construction Master 5 is surprisingly easy to use. It didn't take long for my son to get the hang of it, allowing him to focus more on learning and less on figuring out how to use the tool. Durable and Reliable: It's built to last, which is important for a student's hectic life. He can carry it around campus without worrying about it getting damaged. Overall Impact: It's made a significant difference in his academic life. Every tool that makes his challenging path a bit smoother is invaluable, and this calculator fits the bill perfectly. Final Thoughts: The Calculated Industries 4050 Construction Master 5 comes highly recommended for any student in architectural engineering or similar fields. It's not just a calculator; it's a support system that helps navigate through complex calculations with ease and confidence.
J**E
Love the ease of use and safety it procures me, did it manually before, wouldn’t go back!
J**J
I've used this product for over 30 years and never had a problem. bought this one to replace the 30 year old one
G**S
Très pratique dans les calculs en construction. Pieds,pouces,mètres,millimètres.
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