The GAT Sport Nitraflex range has three products with three jobs. Nitraflex (often called Nitraflex Black) is GAT's stimulant pre-workout for strength and energy. Nitraflex Burn is a thermogenic pre-workout, made for training while dieting. Pumptropic is stimulant-free and made for pumps, so it suits evening training or stacking with Nitraflex. All three are on special at Supps247 right now.
The range at a glance
| Nitraflex | Nitraflex Burn | Pumptropic | |
|---|---|---|---|
| Type | Stimulant pre-workout | Thermogenic pre-workout | Stimulant-free pump |
| Key ingredients (from GAT) | Strength and energy formula; check label for caffeine per serve | CaloriBURN, Nitrosigine, L-tyrosine, L-theanine, Rauwolfia vomitoria root extract | Pump formula, labelled stimulant-free |
| Serves | 20 (465 g) | See label | 20 double-scoop or 40 single-scoop |
| Best for | Daytime strength training | Training during a cut | Night training, stacking, caffeine-free days |
| Price now | $34.95 (was $79.95), Watermelon Dragon Fruit | $39.95 (was $79.95) | $34.95 (Orange was $69.95) |
Nitraflex: the original
Nitraflex is GAT's main pre-workout for strength and energy, with 20 servings in a 465 g tub. It contains stimulants, so check the label for the caffeine per serve before you combine it with coffee or other caffeine. At $34.95 in Watermelon Dragon Fruit, it is one of the cheapest stimulant pre-workouts we stock.
Nitraflex Burn: for training while cutting
Nitraflex Burn combines pre-workout ingredients with thermogenic ones, including CaloriBURN and Nitrosigine, plus L-tyrosine and L-theanine for focus. It also contains Rauwolfia vomitoria root extract, a stimulant-type herb. If you are sensitive to stimulants or have a heart condition, high blood pressure or anxiety, speak to your doctor first. Remember that a pre-workout cannot replace a calorie deficit: read our honest fat burner guide for what thermogenics can and cannot do.
GAT Nitraflex Burn, $39.95. Spicy Mangorita and Tropic Thunderburst are the best-stocked flavours
Pumptropic: stimulant-free pumps
Pumptropic is labelled stimulant-free, and you can take one or two scoops, giving 40 or 20 serves per tub. GAT's label suggests stacking it with Nitraflex. It also works on its own for late sessions when you do not want caffeine near bedtime.
How to stack them
- Daytime strength session: Nitraflex, optionally with Pumptropic for extra pump ingredients.
- Training while cutting: Nitraflex Burn on its own. Do not stack it with Nitraflex, as both contain stimulants.
- Night training: Pumptropic on its own.
Never take two stimulant pre-workouts together, and count all your caffeine for the day, including coffee and energy drinks.
Which should you buy?
Choose Nitraflex if you want an energy pre-workout at a low price, Nitraflex Burn if you are in a cutting phase and tolerate stimulants well, and Pumptropic if you train at night or want a caffeine-free option. For more stim-free choices, see our stim-free pre-workout guide.
Shop the products in this guide
GAT Nitraflex 20 Serves$34.95 GAT Nitraflex Burn$39.95 
GAT Pumptropic Stim-Free$34.95 See the full GAT Sport range and all pre-workouts.
FAQs
What is the difference between Nitraflex and Nitraflex Burn?
Nitraflex is GAT's stimulant pre-workout for strength and energy. Nitraflex Burn is a thermogenic version made for training while dieting, with added ingredients such as CaloriBURN and Rauwolfia vomitoria root extract. Do not take them together, as both contain stimulants.
Does Pumptropic have caffeine?
No. Pumptropic is labelled stimulant-free, so it suits night training or anyone avoiding caffeine. You can take one or two scoops, and GAT's label suggests stacking it with Nitraflex.
Can I stack Pumptropic with Nitraflex?
Yes. GAT's label suggests stacking Pumptropic with Nitraflex. Because Pumptropic is stimulant-free, it does not add caffeine, but follow the directions on both labels.
Is Nitraflex Black the same as Nitraflex?
Yes. Nitraflex Black is a common name for GAT Sport's original Nitraflex pre-workout, which we list as GAT Sport Nitraflex 20 Servings.
Sources: AIS caffeine fact sheet; EFSA scientific opinion on caffeine safety (2015); product labels and brand nutrition panels, checked October 2026.
Order online with Australia-wide delivery, free on orders of $99.99 or more, or visit a Supps247 store in Melbourne, regional Victoria or Brisbane to compare products in person. Members can use our member price match on full-priced items.
Prices and stock were checked on 22 October 2026 and can change at any time. Always read the label and follow the directions for use. If you have a medical condition, are pregnant or take regular medication, check with your doctor first.
