whats the deal with all these tattoo machines are sold on the Internet without points of contact?

plastic sleeve is usually used on frameworks that are conductive to isolate the current frame, however, some frames are made of non-conductive materials with a yoke to connect the coils for wiring, thus completing the circuit.

UK Tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $128.74

UK tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $146.70

100 Pre-made Sterile Tattoo Needles for kit/machine/Ink $24.70

EAGLE Tatouage Tattoo Gun Machine Tip Grip For Needles $4.58

Tattoo Machine Gun Linning Shader 10 Wrap Coils Springs $13.45

Tattoo Machine Gun 10 Wrap Coil Liner Shader Star Frame $44.95

New portable Tattoo Kit 1 Machine / Power/Tube/Needle $20.00

New 1 piece pro tuned art tattoo machine gun M201 $2.25

10x Tattoo machine light $12.00

TATTOO MACHINE GUN RUBBER O RINGS x 100 f/machine tip $4.99

Tattoo Machine Gun With Grip Tips Nozzle Kits Supplies $9.99

TATTOO MACHINE 1" COIL CORE SET WITH PHENOLIC WASHERS $30.99

TATTOO MACHINE 10 1/2 ROUND # 8 COPPER WASHERS $6.99

TATTOO MACHINE 100 # 8 BLACKENED STEEL WASHERS $8.99

TATTOO MACHINE LONG ARMATURE "BA SPEED BAR" $8.99

TATTOO MACHINE 10 1/2 ROUND # 8 BLACK IRON WASHERS $1.99

TATTOO MACHINE 100 BLACK FIBER WASHERS 5/16 COIL CORE $17.99

TATTOO MACHINE 1" COIL CORE SET WITH PHENOLIC WASHERS $30.99

TATTOO MACHINE PIRATE BINDERS VICE KEY THUMB SCREW $44.99

Tattoo Stencil Flash Maker Machine Printer Hi Def Print $135.50

Tattoo Rotary Machine Grip/Back Stem/Nozzle - Silver $16.62

Lucky 7 tattoo machine; used once $26.00

PREMIUM HAND MADE XS TATTOO MACHINE(CHUCK KEY STYLE!!!) $129.00

TATTOO MACHINE GUN GRIP TIPS NOZZLE KIT SUPPLIES PT12 $6.99

Iron Core Coils for Tattoo Machine 10 Wrap Rocket Girl $8.99

HAND MADE TATTOO MACHINE(OLD SCHOOL-NEW P.ROGERS STYLE) $128.00

tattoo machine $60.00

PREMIUM HAND MADE XS TATTOO MACHINE(NEW WRENCH STYLE!!) $129.00

HAND MADE XS TATTOO MACHINE(NEW BIKE GEAR ASSEMBLY!!!!) $129.00

Tattoo Machine Gun Linner Shading Springs 10 Wrap Coils $13.45

TATTOO KIT Power Supply Machine SET 7 Ink Gun Grip New $60.00

Super Power No-noise & Light Tattoo Machine for Needles $43.40

Tattoo Machine Power Supply Needle Ink Skin Kit NEW $59.99

UK tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $146.70

50 Pre-made Sterile Tattoo Needles for kits/machine/Ink $14.81

Tattoo 10 Coil Wrap Motor for machine/kit/Needles/Ink $9.58

3 GUNS TATTOO KIT MACHINE COMPLETE POWER NEEDLE INK EMB $75.95

Iron Core Coils for Tattoo Machine 8 Wrap She Devil $8.99

tattoo machine power supply $102.50

+++TATTOO MACHINE VINTAGE FOOTSWITCH PEDAL+++ $110.00

UK tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $146.70

NEW DESIGN PROF 3 GUNS TATTOO KIT MACHINE COMPLETE INKS $79.95

TATTOO BLOWOUT mags, flash, photos no machine $9.95

EAGLE Tatouage Tattoo Gun Machine With Grip Nozzle $9.99

4 GUNS TATTOO KIT MACHINE COMPLETE POWER NEEDLES INKS B $79.95

Tattoo kit Machine power needles gun ink tips guns new $99.00

Sticker for frame Tattoo Machine Gun Kit Ink Box NEW! $1.95

NEW 3 GUN TATTOO KIT MACHINE LCD POWER TIP INKS NEEDLES $79.95

6 Gun Complete Tattoo Machine Kit Power Needdle Ink Tip $95.00

Custom Made Tattoo Machine Coils 6,8,10, 22,33,47, $29.99

Tattoo Machine Linner Shader Gun Springs 10 Wrap Coils $13.45

USED HAND MADE JENSEN TATTOO MACHINE $61.00

USED 70'S RONIE ACKER TATTOO MACHINE $26.02

100pcs Tattoo Machine Rubber Grommets - Assorted Color $0.99

NEW 4 GUN TATTOO KIT MACHINE COMPLETE POWER NEEDLES INK $84.95

Tattoo Machine Kit 2 guns Ink Power Needle Grip Skin A $49.99

NEW 2 GUN TATTOO KIT MACHINE LCD POWER SKIN INK NEEDLES $70.95

Handmade Tattoo Machine Gun Supply 10 wraps coil C $4.00

3 GUNS TATTOO KIT MACHINE COMPLETE POWER NEEDLE INK EMA $75.95

NEW 1 GUN TATTOO KIT MACHINE POWER NEEDLE 10ml INK GOLD $56.95

NEW PROF FULL TATTOO KIT COMPLETE 3 MACHINES GUNS INKS $115.00

Tattoo Machine Copper Frame 10 Wrap Coils Lining Shade $30.99

NEW 1 GUN TATTOO KIT MACHINE POWER GRIP NEEDLE 10ml INK $56.95

Tight Cut Back Liner Gun Gold Plated Tattoo Machine 10W $13.45

Tattoo Machine Kit 2 guns Ink Power Needle Grip Skin Z $79.99

50 Pre-made Sterile Tattoo Needles for kits/machine/Ink $14.81

UK tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $146.70

100 Pre-made Sterile Tattoo Needles for kit/machine/Ink $24.70

Stainless Steel 'Ultimate' Tattoo Machine $40.00

Stainless Steel 'Ultimate' Tattoo Machine $40.00

Tattoo Tatouage Machine Gun w/ Snake Skin Coils - Grey $45.96

Permanent Makeup Kit Tattoo Eyebrow Machine +70 needles $51.99

STAINLESS STEEL ULTIMATE TATTOO MACHINE $40.00

Quality Black Shader Liner Tattoo Machine Gun Kit B3E $13.45

STAINLESS STEEL 'OVADO' TATTOO MACHINE $40.00

Tattoo Machine Linner Shader Gun 10 Wrap Coils O-Rings $13.45

NEW TATTOO MACHINE GUN GRIP TIPS NOZZLE KIT SUPPLIES A8 $6.99

Stainless Steel Butterfly Tattoo Machine $40.00

Hoodlum Gun Camouflage Walker Custom Tattoo Machine UK $44.90

TATTOO MACHINE BLUE SPRING STEEL, 1' X .018, 1' X .020 $6.99

TATTOO MACHINE BINDING POST 100 FIBER SHOULDER WASHERS $9.99

NEW RED COLOR MINI TATTOO MACHINE POWER SUPPLY KIT $55.99

100 Pre-made Sterile Tattoo Needles for kit/machine/Ink $24.70

Tattoo Machine by RR.Custom Handmade Shader 115 Hz @ 6v $224.57

STAINLESS STEEL 'NEW REAPING' TATTOO MACHINE $40.00

Tattoo Machine Linning Shading Steel Gun Coil Spring $13.45

Revolver Bullet Tattoo Machine $59.99

Wholesale 4 Pro Steel Tattoo Machine Gun Liner & Shader $0.99

UK tattoo Kit 4Gun Machine/DigitalPower/Tube/Needle/Ink $146.70

Steel power Foot Switch f/ Tattoo Tatouage Machine ink $15.99

UPS SHIPPING!LCD DUAL TATTOO MACHINE GUN POWER SUPPLY $48.60

100 Pre-made Sterile Tattoo Needles for kit/machine/Ink $24.70

DANNY FOWLER FUSION TIME MACHINE SHADER TATTOO MACHINE $212.50

Tattoo Machine Coils by: Dart Vaughan $40.00

Sticker for frame Tattoo Machine Gun Kit Ink Box (B) $1.95

24pcs.Tattoo Machine FISH Grips Tubes Aluminum alloy 1" $69.94

10 coil wraps tattoo machines, smile design Tattoo Guns $7.99

HANDMADE 10 wrap Bullet Dial Tattoo Machine Gun NEW $24.98

BRAND NEW! HAND ROLLED SIMON K TATTOO MACHINE COILS $35.00

Sticker for frame Tattoo Machine Gun Kit Ink Box NEW! $1.95