A rotary union , comprising: a housing having a bore in fluid communication with a media channel opening and a piston bore having an open end disposed at a radially offset distance with respect to the bore , the piston bore being fluidly isolated from the media channel opening, and the bore , and is fluidly connected to an actuation port ; a non-rotating seal carrier is slidably disposed within the bore in the housing and having a media channel in fluid communication with the bore ; an actuation arm connected to the non-rotating seal carrier and extending radially outwardly therefrom with respect to the bore , the actuation arm at least partially overlapping the open end of the piston bore ; a piston slidably disposed within the piston bore such that a variable piston volume is defined between the piston and the piston bore , the variable piston volume being fluidly connected to the actuation port , the piston being adapted to extend out from the open end of the bore when a fluid pressure provided via the actuation port is present in the variable piston volume, the piston being configured to urge the actuation arm , and thus the non-rotating seal carrier , to displace relative to the bore when the piston displaces relative to the piston bore ; and a seal disposed around the non-rotating seal carrier and disposed to create a sliding seal between the non-rotating seal carrier and the bore ; wherein the non-rotating seal carrier is arranged to extend relative to the housing when the fluid under pressure is present in the piston bore , characterized in that the piston is configured to releasably abut the actuation arm . a housing having a bore in fluid communication with a media channel opening and a piston bore having an open end disposed at a radially offset distance with respect to the bore , the piston bore being fluidly isolated from the media channel opening, and the bore , and is fluidly connected to an actuation port ; a non-rotating seal carrier is slidably disposed within the bore in the housing and having a media channel in fluid communication with the bore ; an actuation arm connected to the non-rotating seal carrier and extending radially outwardly therefrom with respect to the bore , the actuation arm at least partially overlapping the open end of the piston bore ; a piston slidably disposed within the piston bore such that a variable piston volume is defined between the piston and the piston bore , the variable piston volume being fluidly connected to the actuation port , the piston being adapted to extend out from the open end of the bore when a fluid pressure provided via the actuation port is present in the variable piston volume, the piston being configured to urge the actuation arm , and thus the non-rotating seal carrier , to displace relative to the bore when the piston displaces relative to the piston bore ; and a seal disposed around the non-rotating seal carrier and disposed to create a sliding seal between the non-rotating seal carrier and the bore ; wherein the non-rotating seal carrier is arranged to extend relative to the housing when the fluid under pressure is present in the piston bore , characterized in that the piston is configured to releasably abut the actuation arm . <EOS>