📢 15€ de descuento – 1er pedido

40kg SmartBells™ Ninja Adjustable Dumbbells

€749,00 €849,00
  • One pair replaces 76 dumbbells in 1kg increments
  • Each dumbbell is 38 dumbbells in 1
  • Train Smarter with 1kg increments
  • Adjust weights from 3kg to 40kg
  • Quality checked and come with 36 Months Warranty
  • Precision engineered knurling for advanced performance, grip and comfort.
Loading...
🚚 ENVÍO GRATIS ~ 2 días
🛡️ Garantía de 3 años en mancuernas
😊 Más de 75.000 clientes satisfechos

Entrega y envío

Entrega rápida y gratuita en España, con opciones exprés disponibles. Todos los pedidos se envían desde los almacenes de BrainGain situados en la UE, sin derechos ni gastos de aduana adicionales.

¿Por qué elegir BrainGain?

  • Entrega rápida y gratuita en toda España
  • Calificado como EXCELENTE en Trustpilot
  • Más de 100.000 mancuernas ajustables vendidas
  • Distribuye el coste con Klarna
  • 3 años de garantía de serie

Descripción general

Our 2026 SmartBells™ Ninja are our most advanced adjustable dumbbells.

One compact pair replaces an entire rack of 76 dumbbells.

Fast-change from 3kg to 40kg in 1kg increments. The Ninjas deliver 38 exact weight settings that can be cycled through in under 1 second, giving you total control over your strength-training goals without breaking your workout rhythm.

Eliminate downtime changing weights between sets and unnecessarily large jumps between weights when doing progression.

Matte steel plates provide durability with a refined finish. The brushed aluminium handle is ergonomically shaped with precision knurling for controlled grip under load. A patented safety-lock mechanism secures only the selected weight, while the steel base ensures stability at rest.

The Ninjas are designed for lifters who want to Train Smarter.

Características

3kg–40kg in 1kg increments: 38 precise weight settings for controlled progression. Weight increments include: 3kg, 4kg, 5kg, 6kg, 7kg, 8kg, 9kg, 10kg, 11kg, 12kg, 13kg, 14kg, 15kg, 16kg, 17kg, 18kg, 19kg, 20kg, 21kg, 22kg, 23kg, 24kg, 25kg, 26kg, 27kg, 28kg, 29kg, 30kg, 31kg, 32kg, 33kg, 34kg, 35kg, 36kg, 37kg, 38kg, 39kg, 40kg.

Equivalent to 76 dumbbells per pair: Full rack capability without the space requirement.

Fast twist-handle adjustment: Change weights in seconds without interrupting your workout, with intelligent patented engineering.

Integrated safety-lock system: Only the selected weight is engaged for secure lifting.

Steel plate construction: Durable design built for long-term use.

Brushed aluminium knurled handle: Secure grip with a balanced, comfortable feel.

Stainless steel base: Stable foundation designed for heavy use.

Garantía

Todos nuestros productos vienen con una garantía estándar de 3 años. Durante el período de garantía, repararemos o sustituiremos sin coste alguno los productos o piezas defectuosas debido a defectos de materiales o fabricación, bajo un uso y mantenimiento normales. La información completa sobre la garantía puede consultarse aquí.

  • Up to 38 dumbbells in 1

    Easily adjust from 3kg to 40kg in precise 1kg increments with the SmartBell Ninja™ Adjustable Dumbbells. One compact pair replaces 76 individual dumbbells, eliminating the need for bulky racks while giving you the exact weight you need for every set.

  • Total Body Workouts

    Adjustable Dumbbells can be used for all your home workout needs and exercises including presses, swings, deadlifts, squats, curls, sit-ups, snatch, renegade row, twists, clean & press, thrust and more.

  • Base

    The 40kg Adjustable Dumbbells come with their own tray to facilitate simple weight changes and tidy storage.

Tu cuerpo ya está perdiendo masa muscular

A partir de los 30 años, tu cuerpo pierde masa muscular de forma natural. Sin entrenamiento de resistencia, solo empeora.

3–5 %

de masa muscular perdida por década a partir de los 30 años. Después de los 50, esto se acelera a 1–2 % por año.1

10–17 %

menor riesgo de mortalidad por todas las causas, enfermedades cardiovasculares y diabetes gracias al entrenamiento de fuerza.2

30–60 min

por semana es la dosis óptima: solo 3 sesiones de 20 minutos para obtener el máximo beneficio en longevidad.3

Built Different. Here's the Proof.

We surveyed 659 BrainGain customers across 5 key markets.

90%

said the value justified the price or price wasn't even a concern.*

72%

train 3 or more times per week with their BrainGain dumbbells.*

81%

want to buy more BrainGain products (accessories, supplements, training).*

* Source: BrainGain Customer Survey, February 2026, n=659 across 5 markets.



Rated Excellent on Trustpilot

Don't just take our word for it. Over 1,800 verified reviews from real customers.

★★★★★

Really Happy!

Dean Moran

Really happy with these adjustable weights, easy to put together and smoothly changes weights from 2.5kg all the way up to 40kg.

★★★★★

I previously was using the 24kg

Lee Philpott

I previously was using the 24kg dumbells which are still going strong but have upgraded to the 40kg octagon dumbells, good quality dumbells and look amazing.

★★★★★

Great Quality 40kg Dumbbells

Stephen Hammond

They are great quality and very between 2.5 to 40kg. Perfect for my home gym setup. Quality and ease of use is 10/10 saves so much space and work really well for both me and my girlfriend.

"¡Un punto de inflexión para los entrenamientos en casa!"

Estas mancuernas son simplemente magníficas. Ahorran espacio, tiempo y dinero. Son sólidos y estéticamente hermosos. Además, cabe destacar que no hacen ruido al agitarlos. ¡Un precio increíble!

Michael, Trustpilot España

DIMENSIONES

Base Length: 53 cm

Base & Dumbbell Height: 19 cm

Base Width: 17 cm

Dumbbell Length: 47 cm

Dumbbell Height: 18 cm

Dumbbell Width: 18 cm

Handle Length: 12 cm

Aspectos destacados del producto

Explore las características clave de nuestro 40kg SmartBells™ Ninja Adjustable Dumbbells haciendo clic en los aspectos destacados.

Nosotros vs. Otros

Ni exagerado ni sobrevalorado.
Solo mancuernas ajustables premium diseñadas para durar.

BrainGain
Ajustables Genéricas
Gimnasio / Pesas Fijas
Peso máximo
Hasta 41,5 kg
40 kg
Depende del gimnasio
Ajustes de peso
Hasta 26-en-1
10–17
Fijo
Cambiar peso en 1 seg.
Sin vibraciones al levantar
Sustituye un rack completo
Garantía de 3 años
Soporte Premium