PetTest Insulin Syringes U-40 8mm x 31G with 1/2 Unit Markings, 0.3-cc, 100 syringes

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About This Item

Details

PetTest U-40 Syringes, 31 Gauge x 5/16-in are some of the thinnest, featuring 31-gauge needles. This helps make injection more comfortable for your furry family member compared to thicker 29-gauge U-40 needles. The length of the 5/16 needle also helps reduce the risk of a painful injection to your pets muscle. These syringes are specifically designed to be used with all U-40 insulins. Both sizes, the 0.3-cc and 0.5-cc have easy-to-read unit marking for accurate dosing every time. The needles are extra sharp and lubricated and have a tri-bevel tip for added comfort, while the extra-wide finger grips allow for unmatched control. These syringes come with protective needle and plunger caps.

We directly source prescription medications from manufacturers and wholesale distributors registered with the FDA and licensed by applicable state boards. Guaranteed genuine, and where applicable, backed by the manufacturer.

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Superior Pet Wellness Products

PetTest is a trusted choice for diabetic pet supplies and a powerhouse in supplements for all pets. They offer everything from diabetes monitoring kits and painless lancing devices to gastro support supplements—and everything in between!

Wirelessly Transmit to the PetTest App

Rely on PetTest for accurate, convenient blood glucose monitoring. Their PetLink+ meter wirelessly connects to their innovative app and uses reliable, affordable test strips. They combine high-tech with tried-and-true for easy diabetic pet care.

There’s a Supplement for That...

PetTest leads in pet supplements—all made-in-the-USA, human-grade formulas with no fillers. From supplements to preserve your pet’s vision to urinary tract supplements, trust PetTest for your cat or dog's needs.

Many Choices, for Any Budget

PetTest provides high-quality, accurate, affordable home glucose monitoring solutions for diabetic dogs and cats. They offer meter kits, test strips and supplies for easy, quick results, helping you manage your pet's diabetes in between vet visits.

About PetTest

Since 2015, PetTest has helped manage pet diabetes with affordable, at-home blood glucose monitoring. Now, they offer more than just meters, supplying supplements and many other essential pet supplies you need in your home pet health care arsenal.

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4.5
Rated 4.5 out of 5 stars
253 Ratings
Terms & Conditions

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Comfort

83% Positive

Durability

79% Positive

Ease of Use

81% Positive

Effectiveness

82% Positive

122 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Tilly on Sep 29, 2025
Top 1000 Contibutor

I wish I knew sooner!!

I have been using the 29G syringes on my 14 lb pup because it was what my Primary Vet told me to get. When the Internal Medicine Vet decided to add Toujeo in addition

I have been using the 29G syringes on my 14 lb pup because it was what my Primary Vet told me to get. When the Internal Medicine Vet decided to add Toujeo in addition to Vetsulin, he prescribed the 32G needles. That was when I learned the differences in width of the needles. I am so happy that I found these 31G syringes to use with Vetsulin. They are SOOOO much smaller than the 32G, and my pup hardly notice the needle going into her skin, unlike the 29G. Because the needles are smaller/thinner, there is a greater chance the needle could bend when not careful. I haven't had issues with the needle bending unless my pup moves quickly while I was injecting the insulin, or when I put the needle in the harder part of the rubber stopper in the insulin bottle. Otherwise, they work very well.

Rated 5 out of 5 stars
By Rebeca on Dec 20, 2025

Best Ones

It breaks my heart every single time I have to administer insulin, but these needles seem to be slightly less painful. Highly recommend.

It breaks my heart every single time I have to administer insulin, but these needles seem to be slightly less painful. Highly recommend.

Rated 5 out of 5 stars
By PATRICIA on Jan 7, 2026

Puctuality

His insulin. Unfortunately he passed on Saturday the orders for his care were always on time. Thank you!

His insulin. Unfortunately he passed on Saturday the orders for his care were always on time. Thank you!

Rated 5 out of 5 stars
By Amy on Aug 10, 2025

Size of needle

Our elderly diabetic dog had lost so much weight that her insulin injections were difficult to administer. She didn’t have any fat on her. We tried other syringes

Our elderly diabetic dog had lost so much weight that her insulin injections were difficult to administer. She didn’t have any fat on her. We tried other syringes and they were too long and were painful to her. Ordered these great syringes with the smallest of needles and that has made the biggest difference with her injections and her comfort level since the very first time we started using them. I am able now to give her shots by myself and she is doing great with them. They have been a real game changer!

Rated 5 out of 5 stars
By Madeline on Aug 26, 2025

The small shots for smaller dogs.

Glad the shots were able and delivered right away. Veterinarian was not helpful in knowing there were shorter needles shots for smaller dogs. Did my own research

Glad the shots were able and delivered right away. Veterinarian was not helpful in knowing there were shorter needles shots for smaller dogs. Did my own research and found it on chewy. Thank you.

Rated 5 out of 5 stars
By Lori on Dec 15, 2025

Fast delivery

Thank you for making this transition more comfortable for Toby

Thank you for making this transition more comfortable for Toby

Rated 5 out of 5 stars
By Brenda on Oct 2, 2025

life saver

When my pup was diagnosed with diabetes, I couldn't stand the idea of needles twice a day. These were small and less painful.

When my pup was diagnosed with diabetes, I couldn't stand the idea of needles twice a day. These were small and less painful.

Rated 5 out of 5 stars
By Omega on Dec 15, 2025

The price is wonderful

It helps my doggy that the needle is smaller, He is happier.

It helps my doggy that the needle is smaller, He is happier.

Rated 4 out of 5 stars
By Rhea on Jul 7, 2025

Shorter length and thinner gauge = happy kitty

The length and gauge of these is far better than what I was originally given by my vet for administering Prozinc to a cat. I love the half unit markings too. I had

The length and gauge of these is far better than what I was originally given by my vet for administering Prozinc to a cat. I love the half unit markings too. I had just a handful of defective ones, hence the 4 stars vs 5, but as long as you make sure the plunger isnt crooked and lines are marked on there straight, I will continue to purchase these.

Rated 5 out of 5 stars
By Jack on Jul 31, 2025

What I needed

Insulin syringes are confusing having to match type insulin to the syringes and verifying the unit marking AND the size of the needle. These are just right for

Insulin syringes are confusing having to match type insulin to the syringes and verifying the unit marking AND the size of the needle. These are just right for my small diabetic dog. She hardly feels them when being injected.