Customer Support

This page includes information about ordering, our shipping processes, where to get technical and customer support, terms of service, and many additional important details.


General shipping information, international orders, and local pickups

Customer Service

Order changes, returns, and cancellations


Payment methods, educational discounts, and sales tax information

Technical support

Forums, documentation, and other support


Jobs at Evil Mad Scientist

Contacting us

Contact methods and hours of operation

Other Policies

Privacy, acceptable use, limitations of liability, and acceptance of terms

Shipping and International Orders 

We offer a choice of shipping by USPS First Class mail, USPS Priority Mail, USPS Priority Mail Express as well as UPS options depending on destination. (We do not have Saturday service for UPS as an option.) We charge actual postage rates for shipment, domestic or international, with no added handling fees. For orders to US addresses, we also offer free shipping when your order total is $75 or more. Orders with free shipping selected may be delivered via UPS, USPS, or other carriers at our discretion.

To find shipping options and actual costs for your order, please add the items to your shopping cart. Then, in the cart, enter the destination Country, Postal Code and City, State or Province as needed. You do not need to enter any personal or payment information to view actual postage costs. Particularly heavy orders-- above 60 pounds-- may not be suitable for USPS shipping in a single box; please contact us if our cart is unable to automatically provide pricing for you.

If you would like us to ship an order via UPS on your own account, please select "Pick up at our shop..." as your shipping option at checkout time. Then, contact us with your order number and shipping account information.

We make every effort to keep products in stock and to ship products quickly; most orders for in-stock items ship by the next business day. While many orders do ship on the day ordered, we do not guarantee same day shipment.

We ship all orders complete: if there are one or more backordered items in your order, your order will not normally ship until everything is ready. If you need some items sooner, please place a separate order.

We may not be able to ship to hotels, some mail forwarders and/or PO Boxes depending on location or if there are known issues with the location.

International Orders 
We ship to most countries. USPS First Class mail delivery time varies depending on destination and does not have a guaranteed delivery date. USPS International Priority Mail takes 6-10 business days (up to two weeks) to most destinations worldwide. Shipping by USPS Priority Mail Express or UPS is strongly recommended for all international orders. It is faster, more reliable, and provides tracking information that First Class and USPS Priority mail flat rate envelopes do not. For all orders with a total value of $2500 or more, shipping via UPS is required (USPS will not ship parcels valued at more than $2500).

USPS First Class mail packages and USPS Priority mail flat rate envelopes do not have an invoice affixed to the outside of the package. USPS Priority Mail, USPS Priority Mail Express and UPS packages are shipped with a copy of the invoice enclosed with all required shipping documents. If an electronic copy of an invoice is required, please contact us.

USPS First Class mail and USPS Priority mail flat rate envelopes do not provide consistent tracking services for international orders and is not insured. If a First Class international package or USPS Priority mail flat rate envelope is lost or damaged in transit, that loss or damage is the responsibility of the buyer. (And for that reason, we do again strongly recommend Priority Mail Express international or UPS.)

Please note: Actual value and contents will be declared on customs forms. We can not and will not mark an order as "gift," "sample," or otherwise falsify the value. You may have duties, taxes and/or custom fees charged upon delivery. These fees vary from country to country. You are responsible for paying these fees. So, if your country charges import taxes or fees that are not collected at checkout, please be prepared to pay them. There is no way for us (Evil Mad Science LLC) to calculate fees like these for you; please contact your local authorities if you have concerns about taxes and fees associated with importing products. If you refuse to pay them upon delivery, your package will be returned to us. Upon receipt, we will refund your product (minus shipping fees for both ways).

Customs processing frequently requires an invoice, and we include a copy of the invoice in each international shipment. However, please keep a printed copy of your e-mailed order confirmation in case you need to send it to your customs office or shipping carrier for processing.

Also note that unexpected delays can sometimes occur in customs processing, and that this is also not within our control.

Local Pickup 
Our normal hours for no-contact pickup are Noon to 6 pm Monday through Friday. We are occasionally available outside of those hours by appointment; please use our contact form to inquire.

If you'd like to pick up your order at our store in Sunnyvale, California, please select "Pick up at our shop in Sunnyvale, CA" as your shipping method. We'll e-mail you with no-contact pickup instructions when your order is ready for pickup, usually by the next business day. There's no shipping or handling fee, but we do collect sales tax on orders for local pickup. Our location is 1285 Forgewood Ave, Sunnyvale CA 94089, and we are closed on most mail holidays.

Customer Service 

Making Changes to Existing Orders 

If you need to add additional items to your order, the easiest way to do so is to (1) let us know that you would like to do so-- so that we catch your order before it ships --and (2) place a separate order for the additional items. We can then combine shipping costs and issue a refund for any excess postage paid.

If you would prefer it, we can instead send a credit card invoice for just the additional items and any incremental shipping cost incurred.

Canceling Orders 

Any order for stock items can be canceled for a full refund, right up until it ships. Please contact customer service with your order number if you would like to do so.


Provided that they are still in original condition, we can accept returns on most stock items. If you decide that a product is simply "not for you," please contact us for a return authorization and address. When we receive your shipment, we will issue a refund less shipping costs. Returned orders need to be received within 45 days of the original purchase or a restocking fee may apply. A restocking fee typically applies for items returned not in original condition. We do not accept returns of kits which have been partially or fully assembled.

Please do not return products to us without contacting us and receiving a return authorization first. Return shipping cost is paid for by the customer except for authorized returns of damaged or defective products.


Please contact us right away if you have any problems with your order. We will do everything in our power to correct the situation and make it right, as quickly as possible.

Undeliverable packages 

We do our best to make sure that our products really get to you. However, if all else fails and your package is returned to us as "undeliverable," it is our policy to refund your order less shipping costs.

Payment and sales taxes 

You can place your order directly from our secure payment form using your account, or Visa, MasterCard, American Express, or Discover cards.

By special arrangement we can also accept payments through PayPal, domestic or international wire transfers, purchase orders, or a paper check or money order. Please contact us if you would like to set up an order using one of these alternate means.

There is no minimum order amount; if you're willing to pay for freight, we'll be happy to send you any size order.

Cardholder Data Security Policies
In order to minimize the risk of security incidents, we fully outsource all payment processing to FoxyCart is PCI DSS (Payment Card Industry Data Security Standard) Compliant as a Level 1 Service Provider, and is listed on both Visa and MasterCard's global registries. Anytime you submit payment information via our website, you are submitting through FoxyCart's secure infrastructure. If you opt to save your payment information during checkout, that information is stored at FoxyCart. Neither our staff nor our computers have access to your payment details except for the last 4 digits, the card type, and the expiration date.

Educational discounts
We offer a 10% discount for orders shipping to educational institutions including libraries, makerspaces and hackerspaces. Please use coupon code EDUCATION in the online cart for the discount. If you need a quote showing the discount for a purchase order, please contact us.

Sales Tax and California Orders 
Sales tax will be collected on orders shipped to California addresses unless prior arrangements are made. Sales tax is not collected to orders shipping outside of California.

Value-Added Tax (VAT) is now collected on orders shipping to the UK.

Technical Support 

Product Documentation Site
Our documentation site contains links to product introductions, instructions, schematics, software, and more.

Evil Mad Scientist Blog
Our blog contains product introductions, extended discussions related to our products, examples of their use, a wealth of introductory articles, as well as topics of general interest.

Discord server
The ems-chat discord server offers a place for technical support in a chat-room environment.

Discussion forums
Our discussion forums are a great place to ask questions and share answers.

Contact us
If you can't find what you need, you are always welcome to contact us for personal and comprehensive one-on-one product support — often directly from the people that designed the product. Please note that we are principally an online business and do not offer technical support by telephone.


We are a small family-owned company in Sunnyvale, California. We do not currently have any positions open. When we do, open positions are listed here.

Contacting us 

How to contact us
If you should have any question about our products, or need to contact us about an existing order, or have other questions for us, please use our e-mail contact form or send e-mail directly to contact (@)— This is the best way to contact us.

Additional contact methods:
Voice: (408) 462-1064

Our retail store
Our Sunnyvale retail location will remain closed to walk-in business for the time being. We are offering no-contact local pickup, which you can select at checkout time. If you would like to visit us for a product demonstration, please contact us in advance to make an appointment.

Hours of operation 
We are normally open to the public 12-6 pm, Monday through Friday.

Our retail store is currently closed to walk-in customers. We are, as always, accepting online orders for will-call pickup.

We are closed on the following holidays:


  • Monday, December 26 Christmas Day
  • Monday, January 2 New Year's Day
  • Monday, January 16 Martin Luther King Jr. birthday
  • Monday, February 20 Presidents' Day
  • Monday, May 29 Memorial Day
  • Monday, June 19 Juneteenth National Independence Day
  • Tuesday, July 4 Independence Day
  • Monday, September 4 Labor Day
  • Monday, October 9 Indigenous Peoples' Day
  • Friday, November 10 Veterans Day
  • Thursday, November 23 Thanksgiving Day
  • Friday, November 24 Friday after Thanksgiving
  • Monday, December 25 Christmas Day

Other policies 

We do not spam, we do not accept outside advertising, and we will never sell, trade, or rent your information to anyone. We respect your personal information and in turn strive to earn your respect by treating your personal information with care. We do have a low-volume mailing list, which is strictly opt-in. If you would like to sign up for announcements about new products and specials, you can do so here.

Please read our complete privacy policy here.

Acceptable Use
The acceptable use policy for our site is available here.

External Links
This site contains links to other sites. Evil Mad Science LLC is not responsible for the practices or the content of other web sites.

Limitation of Liability
Evil Mad Science LLC is not liable for any damages caused by any of the site content, whether directly provided by Evil Mad Science LLC or its employees or not.

Updates to this policy
Evil Mad Science LLC has the discretion to update these Terms of Use at any time. When we do, we revise the "Last Revised" date at the bottom of this page. We encourage users to frequently check this page for any changes to stay informed about how we are helping to protect the personal information we collect. You acknowledge and agree that it is your responsibility to review this privacy policy periodically and become aware of modifications.

Your acceptance of these terms
By using this site, you signify your acceptance of these Terms of Use and our Privacy Policy. If you do not agree to this policy, please do not use our site. Your continued use of the site following the posting of changes to this policy will be deemed your acceptance of those changes.

Last revised: November 29, 2022