 This paper investigates the heat transfer enhancement in a horizontal circular tube using hybrid nanofluid, CO, Al2O3 slash distilled water, and fitted with twisted tape under fully developed turbulent flow and uniform heat flux conditions. The experimental test rig includes all the required instruments to study the heat transfer enhancement. The maximum enhancement in the maximum thermal performance factor was 2.18 for a hybrid nanofluid concentration of 1.8%, while for water with twisted tape, it was 2.04. A high nestled number was obtained with a concentration of 1.8% and an enhancement in the heat transfer of about 6.7%. This article was authored by Norhamsa and Sattar Algebraire.