A flexible implement positioner that is lockably installable around abutting flanges of abutting tubes enables an implement, such as a temperature gauge, to be desirably positioned near the joint between the abutting flanges and enable the implement to monitor the joint between the flanges. The implement positioner includes a plurality of body segments hingedly connected to one another in an end to end relationship, with one end including a lock body segment and the opposite end including a lock body segment having a lock lever hingedly mounted thereon, the lock lever positionable in engagement with the lock body segment and pivotal to lockably engage the lock lever when installing the implement positioner on one of the flanges.