Impulse® Foot


The Impulse Foot consists of a composite foot plate attached to a carbon/nylon keel. The foot plate is composed of the high-performing composite material used in the Pathfinder® II Foot. The foot provides high energy return, flexibility, and good toe response. Featuring a recessed keel, the Impulse can be used for endoskeletal, exoskeletal, or Symes applications. Partner the foot with the multiaxial Impulse Ankle for added stability on uneven ground. The Impulse foot carries a weight limit of up to 350 lbs (160 kg).

The Impulse Symes System includes an Impulse Symes Foot and a Symes Adapter Kit. The keel of the Impulse Symes Foot is curved at the same radius as the Symes Socket Adapter, eliminating the need for any type of interface plate and slightly lowering the clearance needed. The Symes Adapter Kit allows angular adjustments (during the alignment phase) as well as length adjustments. The Impulse Symes foot carries a weight limit of up to 250 lbs (115 kg).

Product Highlights:
  • Moderate to High Activity (U.S. Levels 3 & 4)
  • Composite Foot Plate Attached to Carbon/Nylon Keel
  • Available in a Symes version (250 lb weight limit)
  • Use with Impulse Ankle for Added Stability
  • 350 lb Weight Limit (for non-Symes version)
Weight Impulse Foot
Mens: 453 g (1.00 lb)*
Womens: 400 g (.88 lb)*
Impulse Symes Foot
Mens: 494 g (1.09 lb)*
Womens: 441 g (.97 lb)*
Patient Weight Limit Impulse Foot: 350 lb (160 kg)**
Impulse Symes Foot: 250 lb (115 kg)**
Heel Height Women – 3/8” (10 mm) or 1-1/8” (30 mm)
Men – 3/4” (18 mm) or 3/8” (10 mm)
Build Height***
Impulse Foot with Impulse Ankle attached to foot:
10 cm for 3/8″ heel
9.3 cm for 3/4″ heel
Impulse Foot (without Impulse Ankle) to top of interface plate:
4.95 cm for 3/8″ heel
4.25 cm for 3/4″ heel
Available Sizes Women – 22 to 27 cm
Men – 22 to 31 cm
Toe Resistance Very Low, Low, Regular, High, Very High
Heel Insert Densities Soft, Medium, Firm (All three are included with each foot)
Cosmesis Lifelike in Buff, Tan or Medium Brown
U.S. Warranty Information 12 months from date of patient fitting

NOTE for Impulse Symes, Impulse Women’s with 1-1/8″ heel height, and Impulse Mens’ with 3/4″ heel height :
No credit will be issued after 45 days from order date. Exceptions will only be made for warranty returns due to product failures.

U.S. L-Code Suggestion L5976

* Based on size 26 cm foot.
** Body weight plus any loads normally or routinely carried cannot exceed this weight limit.
*** Build height measurements taken for a Men’s size 26 cm foot with WillowWood components. Measurements will vary if using non-WillowWood components.

To order an Impulse Foot, please select the size, side, color, toe spring stiffness, heel height, and adapter.

IMPM-26LB-4M Impulse Foot SAMPLE Part Number
Name Code IMPM IMPM = Impulse – Mens Foot
IMPW = Impulse – Womens Foot
IMSM = Impulse Symes – Mens Foot
IMSW = Impulse Symes – Womens Foot
Size of Foot 26 Mens = 22 to 31 cm
Womens = 22 to 27 cm
Side of Foot L L = Left
R = Right
Color B B = Buff
M = Medium Brown
T = Tan
Toe Resistance 4 1 = Very Low
2 = Low
3 = Regular
4 = High
5 = Very High
6 = Heavy Duty 1 (available for Impulse only)
7 = Heavy Duty 2 (available for Impulse only)
Heel Height M L = Low 10 mm (3/8”)
M = Medium 18 mm (3/4”) Mens only
H = High 30 mm (1-1/8”) Womens only

Impulse® Foot Instructions, English & Spanish
Impulse Exoskeletal Prosthesis Assembly Instructions 
Impulse Symes Socket Adapter Kit Assembly Instructions
Impulse Ankle Instructions  

Fasteners & Torque
M10 x 43 mm Socket Head Capscrew 30 ft-lbs/41 Nm
Pyramid Spacer Block
M10 x 68 mm Socket Head Capscrew 30 ft-lbs/41 Nm
Impulse Ankle
M10 x 32 mm Socket Head Capscrew 30 ft-lbs/41 Nm
English thread for use with all feet
3/8″ x 2.75″ Socket Head Capscrew 30 ft-lbs/41 Nm
Related products:
2LTC-1208 Titanium Foot Pyramid
Impulse Ankle
2LTC-1210 Pyramid Spacer Block
2LAM/W-XXX Shaped Foam Ankle (Included with each foot)
2LSC-1400 Impulse Symes Adapter Kit
2LSC-1430 Impulse Base Plate
(not included in Impulse Symes Adapter Kit)
700-FS006 Symes Nut
2LTE-15XX (part number detail) Impulse Exoskeletal Kit
700-435 Impulse Transfer Block
3F-6CC-002 Interface Plate
3F-6CC-003 Large Interface Plate

Ordering, assembling and aligning the Impulse Foot is discussed in this instructional video.

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