transmission cable 14 preferably includes at least one and preferably two spaced apart pins 50 for insertion within and electrical connection to the control unit 16 the pins 50 are used to establish an electrical connection for any of the electrical components of the handpiece 12 the proximal attachment end 32 also preferably includes a plurality of ports 42 a for connecting to the air and water lines 42 the ports 42 a are preferably fluidly engaged with a corresponding plurality of air and water lines 42 within the control unit 16 the ports 42 a and corresponding air and water lines 42 are preferably arranged to at least provide an air port for cooling the light 66 and other components and a port 42 c for providing chip water the air and water lines 42 run along side of and are preferably radially outwardly spaced from the driving cable 38 and are preferably circumferentially spaced from each other within the cover 40 referring to fig3 and 6 the output shaft 44 is housed within a handpiece coupler 52 at the distal attachment end 34 of the flexible power transmission cable 14 the output shaft 44 has a t shaped distal end 44 a the handpiece coupler 52 includes a coupler backshell 54 that preferably fixedly extends partially over the distal end of the cover 40 a handpiece plug plug 56 extends.