Pro-HD vs Max- What's the difference?

PRO-HD: OUR #1 SELLING COLLAR. FOR THE BUDGET CONSCIOUS. WE DESIGNED A COLLAR THAT IS STRONG ENOUGH TO HANDLE HIGH-ENERGY DOGS, AT AN AFFORDABLE PRICE. THIS COLLAR CAN EASILY WITHSTAND ALL FOUR SEASONS. PROLONGED EXPOSURE TO THE OUTDOORS WILL RESULT IN NORMAL, WEATHER-RELATED WEAR AND TEAR, BUT THEY ARE BUILT TO LAST AND YOU CAN COUNT ON THEM. THEIR INTEGRITY WILL REMAIN INTACT, NO MATTER WHAT YOUR DOG OR MOTHER NATURE THROWS AT THEM.

WHO IS THIS FOR?  THOSE THAT NEED TO OUTFIT AN ENTIRE KENNEL

ELITE MAX: FOR THOSE LOOKING TO STEP UP FROM THE PRO-HD, THE ELITE MAX IS THE ANSWER. WE TOOK EVERYTHING WE LOVE ABOUT THE PRO-HD AND SUPERCHARGED IT. THE ELITE MAX EMPLOYS A TIGHTER WEAVE/HIGHER TENSILE STRENGTH NYLON WEBBING INNER TO GIVE THIS COLLAR A MORE RIGID FIT. THIS FEATURE ELIMINATES ANY POSSIBLE PRESSURE POINTS WHEN WORKING AND MAINTAINS ITS SHAPE. WE WRAPPED THE NYLON WITH HEAVYWEIGHT INDUSTRIAL STRENGTH WATER RESISTANT SEATBELT STYLE WEBBING, GIVING IT UV, WATER, AND ABRASION RESISTANCE. LASTLY, ALL THE HARDWARE HAS BEEN UPGRADED. A TRUE COMMERCIAL GRADE STAINLESS STEEL BUCKLE IS A MAJOR UPGRADE. IT IS VIRTUALLY INDESTRUCTIBLE AND RESISTS CORROSION AND TARNISHING. SIMPLY PUT, THIS COLLAR WILL NEVER LET YOU DOWN.  

WHO IS THIS FOR?  BITE SPORTS, AGITATION WORK, HARD KEEPERS

ELITE MAX V2: THIS COLLAR HAS EVERYTHING THE ELITE-MAX HAS, PLUS AN INNER LAYER OF WATER-RESISTANT SCUBA SUIT NEOPRENE FOR ULTRA COMFORT. THIS ADDITION MAKES AN ALREADY STRONG COLLAR STRONGER, ADDING AN EXTRA LAYER OF REINFORCMENT, FOR A TOTAL OF 6 LAYERS.

WHO IS THIS FOR? BITE SPORTS, AGITATION WORK, HARD KEEPERS, DOGS NEEDING EXTRA CUSHIONING TO REDUCE COLLAR RUB