An assembly for diverting liquid flowing at a first rate through a conduit (C), the assembly comprising: a. a caddy (114, 114A-C) defining a volume (V); b. a clamp , (i) comprising an upper section and a lower section and (ii) being designed to encircle a portion of conduit (C), the upper section being configured to communicate with conduit (C) to permit fluid to flow thereto and therefrom; c. a locking collar for connecting the caddy to the upper section of the clamp; d. an inlet configured, in use, to permit liquid to flow from the conduit into the caddy so as to effect the diversion, via the upper section; the inlet extending into the conduit (C) and having a tapered end (i) presenting an open face to the flowing fluid and (ii) whose trailing edge extends farthest into conduit (C); e. an outlet configured, in use, to permit liquid to flow from the caddy to return to the conduit, the volume (V) defined by the caddy forming part of a low-flow region in which the diverted liquid flows at a rate less than the first rate; the outlet extending into the conduit (C) and having a tapered end (i) opening opposite to the flowing fluid and (ii) whose leading edge extends farthest into conduit (C) ; and f. means for acting upon diverted liquid in the low-flow region, the means selected from the group consisting of treatment, sensing, measuring, sampling, re-diverting, and collecting devices, characterized in that the caddy (114, 114 A-C) forms, in use, interface between various equipments and fluid flowing within conduit (C), and comprises at least two ports (118A-D) in which the means may be plugged to be in contact with the liquid. a. a caddy (114, 114A-C) defining a volume (V); b. a clamp , (i) comprising an upper section and a lower section and (ii) being designed to encircle a portion of conduit (C), the upper section being configured to communicate with conduit (C) to permit fluid to flow thereto and therefrom; c. a locking collar for connecting the caddy to the upper section of the clamp; d. an inlet configured, in use, to permit liquid to flow from the conduit into the caddy so as to effect the diversion, via the upper section; the inlet extending into the conduit (C) and having a tapered end (i) presenting an open face to the flowing fluid and (ii) whose trailing edge extends farthest into conduit (C); e. an outlet configured, in use, to permit liquid to flow from the caddy to return to the conduit, the volume (V) defined by the caddy forming part of a low-flow region in which the diverted liquid flows at a rate less than the first rate; the outlet extending into the conduit (C) and having a tapered end (i) opening opposite to the flowing fluid and (ii) whose leading edge extends farthest into conduit (C) ; and f. means for acting upon diverted liquid in the low-flow region, the means selected from the group consisting of treatment, sensing, measuring, sampling, re-diverting, and collecting devices, characterized in that the caddy (114, 114 A-C) forms, in use, interface between various equipments and fluid flowing within conduit (C), and comprises at least two ports (118A-D) in which the means may be plugged to be in contact with the liquid. <EOS>