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Frequently Asked Questions

Website Questions

I have not received my item in the mail yet, when should it arrive?

We use USPS First Class Mail. It generally takes 5 to 8 business days to receive your product.

However, in some cases it can take up to 14 days for delivery and 21 days for international delivery. Please contact us if you have not received your SuperCool after the allotted time frame. 

What is your email address?

designsteinllc@gmail.com

Why are the video pages blank?

Most likely you are using an outdated or unsupported browser. Our videos are simply embedded YouTube videos from our own YouTube channel. If you are having trouble with the videos on our site, you might try watching them on YouTube.

Do you have any literature I can download for use in my HVAC classes?

Please see the "Educational Aids" tab to the left for all PDF downloads of our notes directly from the tutorial videos.  

Is the SuperCool available in Spanish?

Currently the SuperCool Slide Rule is only available in English.

Please like us on Facebook for all SuperCool updates. 

Is there a SuperCool Slide Rule version that uses Celsius?

The SuperCool Slide Rule does not use Celsius; however, there is a

Fahrenheit to Celsius conversion on the slide rule. 

Checkout/Payment Questions

How can I purchase the SuperCool Slide Rule?

Click the "Buy It Now" button below.

I don't have a PayPal account. Can I pay with a credit card?

You do not need a PayPal account to checkout. Click the "Checkout with PayPal" link at the bottom of the cart page. On the next screen, click the link that says "Pay with Debit or Credit Card". You can then pay with any credit card and will not need to create a PayPal account.

Something weird happened during checkout. Did you get my order/charge my credit card?

If you received a confirmation email from PayPal, then you can be assured that your order was received and is being processed. If you did not make it through the checkout process on PayPal and did not receive a confirmation email, your order was NOT processed and your card was NOT charged. If needed, please use the "Contact Us" tab on the left side of this page to send us a message. 

Why is my credit card being declined?

To help protect your account, PayPal uses a complex screening process for credit card payments. This helps prevent lost or stolen cards from being used for unauthorized transactions. On rare occasions, the screening process affects valid cards. 

A credit card might also be denied if:

  • The card issuer is having technical problems that prevent authorization of a transaction.

  • The card issuer sees a charge that doesn’t fit your normal spending patterns and blocks the transaction to protect you.

  • You’ve inadvertently exceeded the limit on your card.

If you know that your credit card is valid but your payment doesn’t go through, you might want to:

  • Contact your credit card issuer directly. Call the phone number on the back of your card. Ask why your card was declined, and whether you can still use it. If you can still use your card, please try your transaction again. 

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