OBJECTIVES/GOALS: To evaluate whether a low cost, functional dynamic 3-D printed upper extremity (UE) orthosis could be designed, fabricated and used by children with cerebral palsy (CP) with severe unilateral UE involvement and the ability of common standardized instruments to assess its effectiveness. METHODS/STUDY POPULATION: Five patients, ages 13-17 years, with CP and unilateral UE involvement, MACS levels III-IV, were enrolled. Custom forearm thumb opponens orthosis and dynamic upper extremity orthosis (DUEO) were designed and fabricated by a multidisciplinary team for use during 8 one-hour occupational therapy sessions targeting bimanual UE training. Pre- and post-assessments included Assisting Hand Assessment(AHA), Melbourne-2(MA-2), Pediatric Motor Activity Log-Revised(PMAL-R), and PedsQL Measurement Model for the Pediatric Quality of Life Inventory: CP Module(Peds-QL). RESULTS/ANTICIPATED RESULTS: The 3D printed orthotic device is custom fit to the patient based on scans of their arm and is designed with a tensioning system that allows for functional usage of the arm. It incorporates a rigid polymer to provide support and flexible material for comfort where appropriate. Overall, higher post-treatment scores were found for the majority of participants using the custom orthotic. Four made minimal clinically important differences (MCID) in the AHA. Three met MCID scores in subtests of MA-2 (two positive and one negative). Patient-reported outcome improvements were found for PMAL-R for four, but only one met MCID and at least three reported improvements in more than one domain of PedsQL. DISCUSSION/SIGNIFICANCE: Children with CP may often present with UE impairment, yet current therapeutic orthoses only target the progression of contractures and are still limited by cost and discomfort. Our team designed and fabricated a functional, low cost, 3D printed orthosis that showed significant gains in UE function.