Sira
Since 1975 Sira started developing a user friendly, easy to operate & job friendly spring balancer line up. Siraflex spring tool balancers are available to the UK and overseas through YB Components Ltd.

Available in a complete range, Flex balancers manage loads from 0,1 kg to 120 kg targeting the following main features:
- Reduce your job fatigues & downtime.
- Improve your safety, workspace & productivity.
KEEP THE ENVIRONMENT FRIENDLY
Manufactured goods should be tuned with the environment. Flex balancers come alongside this prerogative, exercising great care through out each component: all materials are 100% recyclable. In Type A, the high impact resistant composite housing is made by PP polypropylene and the other components by POM acetyl polyoximethylene polymer (identification codes are stamped directly upon the subject).
PLUG & PLAY
Easy & secure use by everyone. Flex spring balancers are designed to be easy to handle. The spring load can be easily adjusted through the handgrip knob or the specific handle.
APPLICATIONS
Simplify and empower electric and/or pneumatic hand held power tools, first. Then, several other enforcements such as spot welding systems, fitness equipments, and/or wherever you may need a load balance. Available with nylon braided ropes or steel braided nylon coated wires to be selected accordingly to the specific applications.

Flex Type A
FEATURES
- High impact proof composite housing
- 7 models selected for a load range from 0,1 to 3,5 kg
- Adjustable spring load through out an ergonomic hand grip knob
- Adjustable rope stroke Inaccessible hazard components
- Available with nylon braided rope or steel braided nylon coated wire
- Tools in conformity with CE directives
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
SF.0-0,5 | 0-0,5 | 0,3 | 153 | 115 | 50 | 2,3 |
SF.0,5-1 | 0,5-1 | 0,35 | 153 | 115 | 50 | 2,3 |
SF.1-2 | 1-2 | 0,4 | 153 | 115 | 50 | 2,3 |
SF.2-3,5 | 2-3,5 | 0,4 | 153 | 115 | 50 | 2,3 |
Steel Wire
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
SF.0,5-1A | 0,5-1 | 0,35 | 153 | 115 | 50 | 2,3 |
SF.1-2A | 1-2 | 0,4 | 153 | 115 | 50 | 2,3 |
SF.2-3,5A | 2-3,5 | 0,4 | 153 | 115 | 50 | 2,3 |

Flex Type B
FEATURES
- Metal housing
- 14 models selected for a load range from 0,1 to 11 kg
- Adjustable spring load through out a safety removable andle
- Adjustable rope stroke
- Available with nylon braided rope orsteel braided nylon coated wire
- Tools in conformity with CE directives
Model B1
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
FLEX 0,5-1 | 0,5-1 | 0,6 | 165 | 110 | 56 | 2,3 |
FLEX 0,5-1,5 | 0,5-1,8 | 0,6 | 165 | 110 | 56 | 2,3 |
FLEX 1-2 | 1-2 | 0,65 | 165 | 110 | 56 | 2,3 |
FLEX 2-3,5 | 2-3,5 | 0,65 | 165 | 110 | 56 | 2,3 |
Steel Wire
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
FLEX 0,5-1A | 0,5-1 | 0,6 | 165 | 110 | 56 | 2,3 |
FLEX 0,5-1,5A | 0,5-1,5 | 0,6 | 165 | 110 | 56 | 2,3 |
FLEX 1-2A | 1-2 | 0,65 | 165 | 110 | 56 | 2,3 |
FLEX 2-3,5A | 2-3,5 | 0,65 | 165 | 110 | 56 | 2,3 |
Model B2
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
FLEX 3-6A | 3-6 | 1,64 | 230 | 160 | 76 | 2,3 |
FLEX 5-8,5A | 5-8,5 | 1,7 | 230 | 160 | 76 | 2,3 |
FLEX 8-11A | 8-11 | 1,75 | 230 | 160 | 76 | 2,3 |
Nylon Rope (Only On Demand)
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
FLEX 3-6 | 3-6 | 1,64 | 230 | 160 | 76 | 2,3 |
FLEX 5-8,5 | 5-8,5 | 1,7 | 230 | 160 | 76 | 2,3 |
FLEX 8-11 | 8-11 | 1,75 | 230 | 160 | 76 | 2,3 |

Flex Type C
FEATURES
- Metal housing
- 13 models selected for a load range from 1 to 120 kg
- Adjustable spring load
- Adjustable rope stroke
- Steel rope
- Safety device against spring break off
- Tools in conformity with CE related directives
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Cord Length M |
---|---|---|---|---|---|---|
FLEX-3 | 1-3 | 1,4 | 290 | 148 | 69 | 1,5 |
FLEX-5 | 3-5 | 1,5 | 290 | 148 | 69 | 1,5 |
FLEX-9 | 5-9 | 3,4 | 340 | 174 | 136 | 1,5 |
FLEX-15 | 9-15 | 3,8 | 340 | 174 | 136 | 1,5 |
FLEX-22 | 15-22 | 7,2 | 428 | 218 | 158 | 1,5 |
FLEX-30 | 22-30 | 8,5 | 428 | 218 | 158 | 1,5 |
FLEX-40 | 30-40 | 9,8 | 428 | 220 | 188 | 1,5 |
FLEX-50 | 40-50 | 10,4 | 428 | 220 | 188 | 1,5 |
FLEX-60 | 50-60 | 11,6 | 428 | 220 | 188 | 1,5 |
FLEX-70 | 60-70 | 11,8 | 428 | 220 | 188 | 1,5 |
FLEX-90 | 70-90 | 27 | 571 | 264 | 305,5 | 2,1 |
FLEX-105 | 85-105 | 29 | 571 | 264 | 305,5 | 2,1 |
FLEX-120 | 100-120 | 30 | 571 | 264 | 305,5 | 2,1 |

Matic
FEATURES
- Composite housing
- 3 models selected for a load range between 0,5 to 5 kg
- Adjustable spring load
- 6,5×10 mm soft braided polyurethane hose
- Adjustable hose stroke
- Tools in conformity with CE directives
Model | Loading Capacity KG | Weight KG | Length MM | Size/Dimensional Width MM | Thickness MM | Hose Length M | Hose Diameter MM |
---|---|---|---|---|---|---|---|
Matic-M.1,5 | 0,5-1,5 | 1,6 | 285 | 210 | 95 | 1,6 | int. 6,5 / ext.10 |
Matic-M.3 | 1,5-3,0 | 1,7 | 285 | 210 | 95 | 1,6 | int. 6,5 / ext.10 |
Matic-M.5 | 3,0-5,0 | 1,8 | 285 | 210 | 95 | 1,6 | int. 6,5 / ext.10 |