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SirenLabs® ULTRA KARBS™ - Natural | GNC

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ULTRA KARBS™ - Natural (40 Servings)
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ULTRA KARBS™ - Natural (40 Servings)  | GNC
ULTRA KARBS™ - Natural (40 Servings)  | GNC
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$49.99
($1.25 / serving)
  • BOGO 50% Off Mix-and-Match SHOP NOW
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FREE CREATINE! With order of $125+ Apply Code: CREATINE
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FREE CREATINE! With order of $125+. Offer valid while supplies last. Customers will receive a Free GNC Pro Performance Creatine (50 Servings) with qualifying purchase of $125 or more when promo code CREATINE is entered at checkout. Limit one (1) per order, one (1) per customer. Exclusions may apply.
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ULTRA KARBS™ - Natural (40 Servings)

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502700 502700
$49.99
($1.25 / serving)
  • BOGO 50% Off Mix-and-Match SHOP NOW
    close popup
    Offer valid on GNC.com and at participating stores through March 28 2026. Buy 1, get 1 of equal or lesser value 50% off. Mix and match. Select products only. Must add 2 eligible items to cart for discount. Exclusions may apply. See a Coach in store for details or click on "SHOP NOW" to view specific products included in the sale.
FREE CREATINE! With order of $125+ Apply Code: CREATINE
Coupon Code 'CREATINE' Added to Your Cart
FREE CREATINE! With order of $125+. Offer valid while supplies last. Customers will receive a Free GNC Pro Performance Creatine (50 Servings) with qualifying purchase of $125 or more when promo code CREATINE is entered at checkout. Limit one (1) per order, one (1) per customer. Exclusions may apply.
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LOCAL RESTRICTIONS

Due to local weight loss supplement and muscle-building supplements regulations, persons under the age of 18 are prohibited from purchasing this item.

An adult must be present to provide a signature and valid ID upon delivery or pick up in-store.

For New York residents, a $4.99 delivery fee is added in checkout.

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Highlights
Gluten Free
Gluten Free
Sugar Free
Sugar Free
ELITE CARBO-LOADING AGENT
KarboLyn® is specifically designed for the serious athlete looking for a fast, easy, convenient and safe way to load the muscle with readily accessible muscle energy (glycogen). KarboLyn® is a patented carbohydrate that contains a series of very unique properties. Because it passes through the stomach very quickly, it acts like a pump, pulling water and nutrients along with it. This high-tech carbohydrate actually moves through the stomach 80% faster than dextrose or sugar. KarboLyn® also has a higher solution osmolality than dextrose, sucrose, or other carbohydrate powder mixes on the market. This is due to its exclusive patent pending process. KarboLyn® is completely sugar free and is produced using a newly developed "Enzymatic Milling Process." The food sources used to produce the KarboLyn® are corn, potato, and rice, and the finished product is a modified molecular mass polysaccharide that is instantized and absorbed very quickly for maximum biovailability.*

WAXY MAIZE—A SUPER NUTRIENT TRANSPORTER
With a high molecular weight and low osmolarity, meaning it bypasses the stomach and is absorbed by the intestines for immediate assimilation, waxy maize acts as a "super transporter," helping to shuttle nutrients into the body at a higher absorption rate.*

FOR SERIOUS ATHLETES WANTING THAT EDGE
Fast-, medium-, and slow-acting carbohydrates before, during, and after intense exercise are a necessity for serious athletes to improve their performance and maximize their recovery.* ULTRA KARBS™ features patented KarboLyn® and Waxy Maize together to supercharge your pre-workout for more intense gains. ULTRA KARBS™ can also be added to your favorite post-workout protein shake to optimize recovery. USE ULTRA KARBS™ IF YOU ARE A
  • Mass Gainer – to facilitate more lean muscle mass.*
  • High School Athlete – formulated without creatine or stimulants.
  • CrossFit – for a readily available energy source for a long duration of time.
  • Runner/Endurance – to carbo-load quickly for maximum performance.*
  • Bodybuilder – to spike insulin and glycogen levels, and put yourself in a serious anabolic state for muscle hardness, increased fullness, and generating an intense pump.*
Ingredient Amounts
Serving Size  1 Scoop(s)
Servings Per Container  40

Amount Per Serving     % DV

  Calories from Fat 0  

Trans Fat 0  
Cholesterol 0  
Total Carbohydrate 25g   8%
  Dietary Fiber 0g  
Protein 0g  
Calories 100  
Sugars 0  
Sodium 0  
Saturated Fat 0  
Total Fat 0  

ULTRA KARBS™ Blend  25 g   **
KarboLyn® (Homopolysaccharide)  12.5 g   **
Waxy Maise Corn Starch  12.5 g   **

** Daily Value (DV) not established.

FOR PRE-WORKOUT: Mix 1–2 full scoops of ULTRA KARBS™ with 10 oz. of cold water 30 minutes before exercise/training. Stack ULTRA KARBS™ with any pre-workout supplement to maximize your performance and endurance.*

FOR POST-WORKOUT: Mix 1–2 full scoops of ULTRA KARBS™ with 10 oz. of cold water and use immediately following your exercise/training. You can also add ULTRA KARBS™ to your favorite protein or post-workout drink immediately following exercise for greater recovery and to fight fatigue.*

NOTE: ULTRA KARBS™ is an instantized formulation and is designed to mix and dissolve easily in liquids. Due to settling, a natural occurrence with powders, variations in the powder height level may vary from bottle to bottle. Additionally, powder density may be affected as a result of the settling, which may cause slight variations in the scoop serving size. To be used as part of a physical conditioning program.

Warnings SEE MANUFACTURER'S LABEL FOR ADDITIONAL PRODUCT INFORMATION AND SUPPLEMENT FACTS PANEL.
VOIR L'ÉTIQUETTE DU FABRICANT POUR L'INFORMATION SUR LE PRODUIT SUPPLÉMENTAIRE ET LE PANNEAU DE FAITS SUR LES SUPPLÉMENTS
Mfd. Exclusively for SirenLabs™ 4509 South 143rd Street, Suite 1 Omaha, NE 68137
Note: This product cannot be shipped to Canada, Japan
Shipping Methods And Costs

At checkout, you will be prompted to choose a shipping method for your item(s). Shipping costs are dependent on the items in your order and the shipping method you select. Your total shipping charges will automatically compute during checkout prior to the completion of your order.

If you are shipping within the United States, you will have the option of upgrading your shipping method for faster delivery (Standard, Expedited or Overnight). If you choose to upgrade your shipping method, your order must be received and clear credit authorization by 4:00 p.m. EST or your order may not be processed until the following business day. Business days are Monday-Friday, excluding observed holidays within the United States.

Shipping Rules and Restrictions
  • Orders are shipped on business days only. Business days are Monday-Friday, excluding observed holidays within the United States.
  • You will not be charged for any item until it is shipped to you.
  • Please call a Customer Service Specialist at 1-877-GNC-4700 if you have any questions.
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We want you to be fully satisfied with every item that you purchase from www.gnc.com or from an Authorized GNC Retailer. If you are not satisfied with an item that you have purchased, you may return the item within 30 days from the order date for a full refund of the purchase price, minus the shipping, handling, gift wrap, or other charges.

The item must be returned, unused or used, in good condition, in original boxes (whenever possible), and with all paperwork and accessories to ensure full credit.

Our Standard Return policies do not apply to all items. For a list of exceptions to our Standard Return policies click here.

From the Brand
This information is provided from the brand owner, not GNC. GNC assumes no liability for inaccuracies or misstatements regarding any product. view full disclaimer
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Content on this website is for general reference purposes only and is not intended to substitute for advice by a physician, pharmacist, or other licensed health care professional. You should not use the information presented on this website for self-diagnosis or for treating a health problem.

While GNC strives to ensure this page’s accuracy, actual product packaging and materials may contain additional and/or different ingredient, nutritional, or proper usage information than the information displayed. We recommend you read the labels, warnings, and directions prior to using or consuming a product

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