To check the status of your order, please login or create an account here. Locate the order in your account to view the order status.

At checkout you can select the option for Premium (3-8 business days) or Express Shipping (2-3 business days) for a fee. Orders over $99.99 receive free Standard shipping (7-14 business days).

We want you to love your stethoscope, so if you would like to make an exchange, please contact us with the order number at customer.service@mdfinstruments.com. If there is a price difference, we will refund the difference on the original order or charge the difference if you would like to upgrade your MDF® Instrument.

We give you 90 days to try our products, and if you don't love your MDF Instruments® product, simply initiate a return by contacting our customer service department at customer.service@mdfinstruments.com.

Upon receipt of the returned product, we will issue a refund for the purchase price of the item(s), not including the original shipping charges. Please give us a few days to process your return. Stethoscopes that have been engraved are not covered under the 90 Day Return policy. If you have received a stethoscope with an engraving error, please let us know and we will replace it. If your item arrives damaged or contains a manufacturer's defect, it is covered under our Lifetime Warranty™.

If for any reason you would like to exchange a product outside of our 90 Day Return policy please contact us. All returns must have an RMA number (Return Merchandise Authorization), so please contact us to receive this number. If an RMA number is not obtained prior to the return, a $5 handling fee will be applied. To request an RMA, please email customer.service@mdfinstruments.com and include the following information: original purchase number, name and the reason for the RMA request.

Returns must be shipped within five business days after the RMA is issued. All returns must be received within 10 business days of the RMA being issued. We are unable to refund any import duties/tariffs, original or return shipping costs.

Bulk returns may be subject to a 15% restocking fee.

More information

The shipping time will depend on the shipment method and delivery location. If you are uncertain if you will receive your product in time, please give us a call at 1.818.357.5647 and remember to take into consideration an additional three business days for processing.

- Express Shipping occurs after the order is processed and does not guarantee arrival in 2 days
- Engraving orders may take up to 10 additional business days to process.
- The final delivery time will vary based on the shipping carrier, service and delivery location.
- If your order lies on a weekend, your order will be processed on the next business day (Mondays).
- We do not require an adult signature for deliveries.
Free shipping is only available within the continental U.S. Shipments to Alaska and Hawaii do not qualify for our free shipping offer. We have the ability to ship to addresses within the 50 United States (including DC) via FedEx or United States Postal Service (USPS). We are not responsible for lost or damaged packages (please contact FedEx or USPS if your package has been lost or stolen). All shipments addressed to P.O. boxes will be shipped via USPS.
- MDF Instruments reserves the right to cancel any order and will notify you immediately if we decide to do so (using the contact info you provided). 

Yes, our Free-Parts-For-Life™ Program is really free.

Free-Parts-For-Life™ shipments will be sent to the shipping address on the original order or location of purchase. If you have moved to another country other than the original shipping location, please read our guidelines. 

Simply complete our online Free-Parts-For-Life™ form to register you instrument and order free parts or call us at 818.357.5647 and we'll get you taken care of.

The parts include our ComfortSeal™ Eartips in three sizes (small, medium and large), ID Tag, diaphragms, retaining rings and non-chill rings

Our Free-Parts-For-Life™ Program shipments to the US and Canada are sent via USPS and may take up to 14 business days to process and arrive, depending on your normal postal service speed. For shipments to Canada, Hawaii, Alaska and Puerto Rico please allow up to 25 business days. International shipments may take longer depending on the location of the closest distribution center and shipping destination. Free-Parts-For-Life™ Program shipments do not include tracking information. After making your parts request online, you will receive a confirmation message and your parts will be shipped in 5-7 business days from placing the request.

We are here to help.  Check out our videos that will guide you through, step by step for each part. 

Do not worry because we are happy to send you more at no cost, as part of our Free-Parts-For-Life™ Program. We offer replacement ComfortSeal™ Eartips in clear and black in three sizes (small, medium and large).

We offer custom engraving on the chestpiece for select stethoscopes ordered from our US website. You will see the option to engrave on the product page for any model that applies.

You can also check with your local jeweler who offers engraving. Engraving the stethoscope chestpiece will not effect the sound quality if engraved properly, nor the Lifetime Warranty™.

We recommend using 70% isopropyl alcohol pads or on a cotton ball or swab, to clean the eartips and wipe the diaphragm and chestpiece of your stethoscope. To clean the tubing, use warm water with mild detergent on a clean rag or towel, to wipe the stethoscope tubing and dry. Do not soak the chestpiece or allow liquid to enter. To learn more, watch this video tutorial.

Due to the nature of the material of stethoscope tubing, it can easily pick up dyes from scrubs or pen ink and become stained. If you have tried cleaning the tubing and your stethoscope has become permanently stained, please feel free to contact us and we will try to find a solution that meets your needs.

All MDF Instruments® Stethoscopes (excluding the Singularis® line) come with a Lifetime Warranty™ and Free-Parts-For-Life™ Program. Our Lifetime Warranty™ covers the entire stethoscope from issues related to the process of manufacturing, and does not cover lost or stolen items, or aesthetic issue such as dye transfer or pen ink.  

There are a few things you can check if you can't hear out of your stethoscope. First, check that the diaphragm is securely attached to the chestpiece with no gaps between the retaining ring and forms a tight seal like a drum. Make sure the chestpiece is rotated so that the green dot indicator on the stem if facing the side of the chestpiece you would like to use. Next, check that the pre-angled headset is facing forward so that the eartips are in line with the natural angle of your ear canals. Check if any part of the headset feels loose or broken inside of the tubing or if there are any punctures or tears in the tubing and it feels flexible and soft. If you are still not able to hear of your stethoscope, don't hesitate to contact us.

The green dot located on the stem of the chestpiece will indicate which side of the chestpiece is active. The stem will rotate to the diaphragm or bell side with the green dot indicating the open channel.

A dual head stethoscope will allow you to listen to both high and low sound frequencies. All MDF Instruments® Stethoscopes will feature a True Bell and a True Diaphragm to consistent and easy auscultation. The bell side is designed to pick up low frequency sounds and the diaphragm side of the chestpiece is designed for high frequency.

To make a Lifetime Warranty™ request for a replacement headset and tubing, please register your stethoscope if you haven't already. You can register and make the request online using our Lifetime Warranty™ form or feel free to contacts us and we will complete this process for you. Once you receive the replacement headset and tubing, you will remove your chestpiece by pulling it firmly from the end of the damaged tubing. Then, reinsert the chestpiece into the end of the new tubing.

Your Pulse Time® clock requires a LR-41 battery, available at any local drugstore or jewelry/watch store. Watch a video below.

Remove your existing retaining ring and diaphragm by pressing the retaining ring down towards the chestpiece with your thumbs until it pops off. This video demonstrates the process.

To remove the non-chill ring, push the edge of the ring over and down the bell of the chestpiece. The entire ring should stretch over and off the bell. Click here to watch a video that will walk you through the process.

Take your new retaining ring with the diaphragm installed and with the MDF® Instruments logo facing up, place it on top of the diaphragm side of the chestpiece. Using your thumbs, slowly work around the edge of the ring to push it down and over the edge of the chestpiece to fit snug. You may hear it snap into place. Inspect the chestpiece to make sure the diaphragm does not have any gaps or isn't popping out from the edge of the retaining ring.

Take your replacement non-chill ring and start by fitting the edge of the ring around the bell of the stethoscope. Using your thumbs, work around the ring to stretch it over and down the bell. Check out this video showing the process.

If your sphygmomanometer is leaking air, it could be possible that the connections have loosened. Check the connection from the tubing to the gauge to make sure it is secure and the end of the tube is flush with the gauge. Also check the connection from the tubing to the bladder of the cuff to make sure it is secure and no air can escape. Next check the connection from the tubing to the bulb and make sure the end of tube sits flush with the metal end of the bulb.

Fully inflate the cuff and listen for a hissing sound. This could indicate an air leak. Check for punctures in the bladder, tubing and bulb. If you think you have an air leak, please contact us to place a Lifetime Warranty™ request. You may make the request online using our online Lifetime Warranty™ form.

Check that the valve release on the gauge is working properly and will allow for a release of air when turned open. If this is still not working, please let us know by contacting us directly.

Using the wrong patient blood pressure cuff size will likely yield an incorrect blood pressure reading. All of our sphygmomanometers will come with an adult sized cuff, but we also offer the following cuff sizes separately, so you can ensure blood pressure reading accuracy.

Upper Arm Circumference Ranges by Cuff Size:

Thigh: 40CM - 65CM (thigh or upper arm)
Large Adult: 33.5CM - 50CM
Adult: 25CM - 40CM
Pediatric: 19CM - 27.5CM
Infant: 14CM - 20CM
Newborn: 10.2CM - 16CM

To clean your blood pressure cuff, remove the bladder, then wash with warm water and mild detergent. Allow to air dry before replacing the bladder. Bladders can be cleaned with a rubbing alcohol solution and clean cloth.

 To make a Lifetime Warranty™ request for gauge calibration, simply complete the Lifetime Warranty™ form and we will take care of the rest.  If you have not registered your sphygmomanometer, you can also register on this same form.  An agent will reach out to you shortly with information to return your gauge for calibration or replacement.

First verify that your penlight has working AAA batteries installed. If you replace the batteries and it's still not working or it has a defect not associated with the batteries, please contact us directly.

MDF® penlights are warranted to be free from defects in material or craftsmanship. Penlights with defects in material or craftsmanship will be replaced or repaired without charge as long as the defect is reported within one year of the original purchase. The MDF® 621 LUMiNiX® is warranted to be free from defects in material or craftsmanship. LUMiNiX® with defects in material or craftsmanship will be replaced or repaired without charge as long as the defect is reported within two years of the original purchase.