The Ezepak vaccine holster is made for ease of use and operator comfort. No messing around with those vaccine-pack neck strings. Just slip the pack into the holster for quick change-overs. The shoulder strap prevents the pack swinging about when working. Easy to get on and off. Pockets on pack for product label and needles packet. NB: The Vaxiholster does not include the belt holster or vaccinator shown above.