The Clearly Outdoors Smart Stop Micro Bobber Stop and Refill Combo Pack Includes 48 Micro Stops and Installation Tool to attach the stops to the line. The Smart Stop Micro is a hard plastic bobber stop that snaps onto your 2lb-12lb monofiliment line using the included tool. It is designed to replace and eliminate both the tie on knot and bead as well as the need to thread your line through your stop. Simply set your line into one of the slots of the smart stop bobber stop, give the stop a pinch with the included tool and a twist, and it's on - ready to go.