HARFINGTON 4pcs Metal Straight Ruler 20cm Metric SAE Aluminum Alloy Measuring Rulers Scale Tools with Hole for Measure Study Reading Classroom Office, Blue - color: Blue, size: 20cm
HARFINGTON 4pcs Metal Straight Ruler 20cm Metric SAE Aluminum Alloy Measuring Rulers Scale Tools with Hole for Measure Study Reading Classroom Office, Blue - color: Blue, size: 20cm
About this item
- Size - Straight ruler measuring range: 20cm / 7.87"; system: metric and SAE; minimum scale: 1mm / 0.04"; width: 28mm / 1.1", package include: 4pcs x straight rule.
- Material - The straight ruler is made of aluminum alloy, making it anti-rust and anti-corrosion, as well as hard and durable. This construction ensures that it is not easily deformed or damaged, thereby ensuring measurement accuracy. Anodized surface treatment, ensuring lightweight construction while significantly enhancing its wear resistance and anti-corrosion performance.
- Feature - The ruler features ink printing technology on its surface, ensuring that the scale is clear and sharp, remaining non-fading and non-blurring even after long-term use. It has a dual-scale design, and the back is carefully printed with a complete set of conversion formula for metric and SAE units, allowing beginners to quickly master unit conversion skills. Additionally, it includes a hanging hole design for convenient storage and accessibility.
- Application - The dual-scale straight ruler is widely used in geometric drawing, plane drawing, composition planning, and mathematical chart drawing; it is suitable for classrooms, architectural design, art design office occasions, and other work environments that require precise measurement or drawing.
- Note - Try to avoid collision of the ruler with hard objects to prevent damage to the scale and affect the measurement accuracy. Please do not bend the folding ruler to maintain its accuracy and stability.
Overview
- Brand: HARFINGTON
- Color: Blue
- Unit Count: 4 Count
- Number of Items: 4
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Low stock: 10 left
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Reviews
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Hannah Miller — Seattle, Washington
I ordered several science activity supplies for projects at home. The product descriptions made it easier to compare the available options, and everything fit neatly into our learning space. Stemora made finding tools for hands-on activities feel simple and organized. -
⭐⭐⭐⭐⭐
Daniel Foster — Austin, Texas
I found a useful selection of electronics and robotics accessories for a beginner project. It was convenient to browse related components in clearly organized categories. I would consider shopping here again when planning another maker activity. -
⭐⭐⭐⭐⭐
Lauren Bennett — Denver, Colorado
The measurement and observation tools I selected worked well for the classroom activities I had planned. I especially appreciated being able to review the product details before ordering and choose items that matched the lesson requirements. -
⭐⭐⭐⭐⭐
Jason Parker — Portland, Oregon
I purchased a few storage items and small tools for organizing my maker workspace. The products helped keep components, wires, and project materials easier to sort and access. The overall shopping experience was straightforward and convenient.
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FAQ
What types of products does Stemora offer?
Stemora offers supplies for science experiments, microscopy, biology learning, measurement, laboratory organization, electronics, robotics, coding education, 3D printing, maker projects, and classroom activities. Available products and specifications may change over time.
Are Stemora products suitable for children?
Recommended ages vary by product. Please review the product description, manufacturer guidance, included warnings, and required skill level before purchasing. Products containing small parts, tools, electrical components, glass, or chemicals may not be suitable for young children.
Is adult supervision required?
Adult supervision is recommended for children and students, especially when using electrical components, sharp tools, heated equipment, glassware, small parts, or experiment materials. Customers are responsible for following all product instructions and safety precautions.
Can these products be used at home and in classrooms?
Many products may be suitable for classrooms, home learning, science projects, maker spaces, and hobby activities. Suitability depends on the specific product, learning environment, user experience, and intended activity.
How can I check what is included with a product?
Please review the product title, description, specifications, images, package quantity, and included-components section before ordering. Items shown for demonstration or scale in product images may not always be included.
How do I know whether an electronic or robotics part is compatible?
Check the listed dimensions, voltage, connector type, board compatibility, operating requirements, and supported platforms. Compatibility is not guaranteed unless it is specifically stated on the product page. Contact us before ordering if you need clarification.
When will I receive tracking information?
Tracking information is generally provided within 3–5 business days after an order is confirmed. In some cases, processing may take approximately 7–8 business days. Delivery may require an additional 4–5 business days after tracking becomes available, depending on the carrier and destination.
Why did my order arrive in separate packages?
Products in the same order may be shipped from different fulfillment locations. As a result, items may arrive separately and have different tracking numbers. You will not be charged additional shipping fees solely because an order is divided into multiple packages.
Can I change or cancel my order?
Contact us as soon as possible at vaioamaonaoak@gmail.com. We will try to assist, but changes or cancellations cannot be guaranteed once an order has entered processing or has been shipped.
What should I do if an item arrives damaged, defective, or incorrect?
Contact us promptly at vaioamaonaoak@gmail.com with your order number, a description of the issue, and clear photographs of the item, packaging, and shipping label. Please retain the product and original packaging while we review your request. Eligibility and available resolutions are subject to our Return & Refund Policy.
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