The availability of low-cost accelerometer technology has led to a surge in consumer-based physical activity monitors (Lee et al., 2014). A top leader in this market is Fitbit (Dolan, 2014). Fitbit's activity tracking devices allow for self-monitoring and other features related to behaviour change (e.g., goal setting) called behaviour change techniques (BCTs). It has been determined that one popular wrist-worn device, the Fitbit Flex®, incorporates 20 BCTs (Lyons et al., 2014). The purpose of this study was to explore user's experience with the Fitbit Flex® as it relates to physical activity behaviour and BCTs. Participants (n=28, 82.1% female, 18-71 years old) completed an online survey assessing: (1) demographics and Fitbit acquisition, (2) step volume (number of steps for the past week and the first week of use), and (3) user's perceived importance and/or frequency of use of the 20 BCTs. Participants had used the Fitbit for an average 5 months and there was a significant increase of almost 2000 steps (p = .003) from the first to the past week of use. The BCTs rated among the highest for perceived importance for physical activity behaviour (i.e., step volume) were feedback, self-monitoring, and goal setting. The BCTs related to feedback or reward of outcomes (i.e., weight loss) and social features (e.g., social support) were rated on the lower end of importance/frequency. Overall, the present study contributes to understanding the influence wearing a Fitbit Flex has on physical activity as well as the importance of certain BCTs, which has implications for future physical activity promotion and product development.