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Raytraced image of two jack plugs, one mono, the other stereo. Numbers on details added, and image cropped afterwards in a graphics software package.
Numbers indicate:

1. Sleeve - usually ground
2. Ring - Right-hand channel for stereo signals, negative phase for balanced mono signals, power supply for power-requiring mono signal sources
3. Tip - Left-hand channel for stereo signals, positive phase for balanced mono signals, signal line for unbalanced mono signals
4. Isolating rings

Rendered with POV-Ray (see http://www.povray.org/) - below is the scene description for this image

 /*
 ======================================
 "Jack"- or "Tip-ring-sleeve"-type plug
 --------------------------------------
 Created by Søren Peo Pedersen - see my
 user page at
 http://da.wikipedia.org/wiki/Bruger:Peo
 ======================================
 */
 
 #declare Metallic=texture {   // Texture for
     pigment {color rgb .3}    // metallic parts
     finish {                  // of the jacks
         reflection .7
         phong 1
         phong_size 60
         ambient .5
         diffuse .5
         metallic
         }
     }
 
 #declare Isolator=texture {   // Texture for insu-
     pigment {color rgb 0}     // lator between tip,
     finish {                  // ring, and sleeve
         reflection .5
         phong 1
         phong_size 20
         }
     }
 
 #declare Spotty=pigment {     // Spotty pigment
         bozo                  // for surroundings,
         color_map {           // to enhance the
             [0 color rgb 0]   // reflective parts
             [1 color rgb 1]   // of the plugs
             }
         scale .3
         }
 
 sky_sphere {                  // Make for "surroundings"
     pigment {
         gradient y
         pigment_map {
             [0.0 color rgb 1.0]
             [0.12 color rgb 1.0]
             [0.2 Spotty]
             [1.0 Spotty]
             }
         translate <0,-.5,0>
         scale 2            
         rotate <-90,0,0>
         }
     }
 
 #macro Jack_plug(StereoFlag)  // Common macro for mono & stereo plug
 
 union {             // Cable extending from
   sphere_sweep {    // rear end of the plugs
     cubic_spline,5,
     <0,100,0>,2.7
     <0,-40,0>,2.7
     <20,-90,-10>,2.7
     <-0,-240,-40>,2.7
     <-0,-290,-90>,2.7
     
     pigment {color rgb .5}
     finish {
       ambient .5
       diffuse .5
       }
     }
     
     // Conical "sleeve" where the cable enters the jack:
     cone {<0,-24.5,0>,5,<0,-40,0>,3 pigment {color rgb .5}}
     torus {3,1 translate <0,-40,0> pigment {color rgb .5}}
     
     // Cylindrical, dark "body"
     cylinder {<0,-24.5,0>,<0,-24,0>,5.5 texture {Isolator pigment {color rgb .2}}}
     torus {5.5,.5 translate <0,-24,0> texture {Isolator pigment {color rgb .2}}}
     cylinder {<0,-1,0>,<0,-24,0>,6 texture {Isolator pigment {color rgb .2}}}
     torus {5.5,.5 translate <0,-1,0> texture {Isolator pigment {color rgb .2}}}
     
     cone {0,4.5,<0,-.5,0>,5.5 texture {Metallic}} // Metal "base" of plug
     
     cylinder {<0,0,0>,<0,   // "Sleeve" part of the plug
       #if(StereoFlag !=0) 15.3 #else 21.2 #end
       ,0>,3.1
       texture {Metallic}
       }
     
     #if (StereoFlag != 0) // If rendering the stereo (3-way) version:
       cylinder {<0,15.3,0>,<0,16.3,0>,3.1 texture {Isolator}}   // Add an extra, narrow isolator
       cylinder {<0,16.3,0>,<0,21.2,0>,3.1 texture {Metallic}}   // and the ring
     #end
     
     cylinder {<0,21.2,0>,<0,22.8,0>,3.1 texture {Isolator}}       // Wide isolator
     // Cylindrical section right behind the tip:
     cylinder {<0,22.8,0>,<0,23.5066144,0>,3.1 texture {Metallic}}
     
     merge {   // The tip with "neck" and conical end
         cone {<0,31.2,0>,0.8,<0,27.7156,0>,3.0111}
         torus {2.5,.6 translate <0,27.4,0>}
         cone {<0,23.6,0>,0.8,<0,27.0844,0>,3.0111}
         
         difference {
             cylinder {0,<0,1.638,0>,2.866144}
             torus {2.866144,1.066144 translate <0,1.066144,0>}
             translate <0,23.8,0>                    
             }
         torus {2.8066144,0.2933856 translate <0,23.5066144,0>}
         
         texture {Metallic}
         }
     }
 
 #end  // End of macro
 
 // Show a mono and a stereo jack:
 #object {Jack_plug(1) rotate <0,-20,0> rotate <-40,0,-100> translate <0,11,0>}
 #object {Jack_plug(0) rotate <0,20,0> rotate <-40,0,-100> translate <0,-8,0>}
 
 light_source {<-10000,5000,-10000> color rgb 2}            
 camera {location <0,0,-80> look_at <0,0,0> angle 50}

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