51... i do not think the vackupack could contaminate the bag...you have it twisted, it was the sinbo unit i was reffering to as more likely to being able to spread contaminants. it is by shere contact that the sinbo could introduce contaminats inside the bag, ck out the operating instructions of the sinbo unit... i did and all i am saying is the sinbo, the nozzle is on the product side of the bag, it is different than the others and the nozzle extends into the bag on the product side, then is retracted to complete the seal. so if there are any contaminants on the nozzle then you could be introducing them into the bag, on the Vmachine the nozzle does not enter the product side of the bag and it would be highly unlikly that contamination would get into the bag as you are pulling a vacum.