Truefin: engineered for performance, made in the USA.

Innovation of spines brings unparalleled efficiency to divers.

MARESH Patents

Truefin LLC is a company based in West Linn, Oregon, USA.

The genesis of the Truefin swim fin came from earlier theoretical applications regarding titanium spinal implant devices (US 10,702,312) for treating biological spine deformities, and also included technology to replace implanted solid long rigid metal bars with implanted articulating artificial spines in order to stabilize and strengthen the biological spine while improving comfort for the user. For non-operative treatment of scoliosis, experimental back braces (pending) were also constructed which utilized artificial spine technology, where a back brace is gently biased toward centering lateral alignment to attempt to correct bending of the biological spine in the coronal plane, while allowing the biological spine to articulate and flex nearly unrestricted in the sagittal plane.  By allowing the biological spine to articulate in this manner rather than be rigidly constrained is expected to accelerate correction and also provide comfort for the user. This was accomplished with artificial spines which includes: (1) implantable keyed bushings, or (2) a non-implantable linear configuration of bushings having concave and convex surfaces under compression; where both embodiments allow a central cable tensile member to flex in only the sagittal plane.  An alternative approach to correct sideways curvature of the biological spine is known as vertebral body tethering (VBT or spinal tethering), and is showing promise if over-correction of the spinal deformity may be controlled. More research is necessary, and all patents issued or yet to issue related to these apparatus by Maresh Engineering, LLC are to be passed to the public domain, and are free to use by any individual or entity interested.

Above: Titanium artificial spines having a central titanium cable tensile member.

Simultaneously, an efficient oscillating fin upper body propulsion apparatus (US 10.343,754) was developed for handicapped users (adaptive divers) without use of their lower body in order to take advantage of the therapeutic benefits of a body's increased output of serotonin which occurs at depth while scuba diving.  Users of this upper body apparatus developed speeds approaching and in some cases exceeding users of traditional foot swim fins. These patents are to be passed to public domain, and are free to use by any individual or entity interested.

Directing attention to a consumer category apparatus, and recognizing the potential to improve the efficiency of lower body propulsion, efforts began to advance the design of traditional swim fins.  Generally, the most important property of a swim fin is efficiency and angle of attack, and after several evolutions of design a variation of the original artificial spine was developed specifically for Truefin swim fins thereby offering multiple advantages of speed, efficiency, and reduced stress over traditional spineless fins.

Patent Information

• U.S. patent # 9,764,192

• U.S. patent # 10,071,288

• U.S. patent # 10,226,668

• U.S. patent # 10,525,307

• U.S. Patent # 11.135.480

• Other patents issued and/or pending in the United States

• China - Patent Pending CN ********* A

TRUEFIN ® and SPINEFORCE ® are registered trademarks of Maresh Engineering, LLC