pile pwd 701 review check the latest price and exclusive prime membership offers from the amazon link given in the description pile is known more for manufacturing affordable car speakers but the pile is among the most popular car alarms on the market as with high-end alarms like the viper and python this security system features a six-stage 120 decibel siren with a dual stage sensor however it has something those other car alarms don't an anti-carjacking feature if all you want is a car alarm this is a good option though there are more affordable options just as capable this makes it one of the most affordable car alarms on the market it also explains why it's one of the most popular car alarms available on amazon that said the avatal is cheaper more popular and higher rated among amazon users with a dual stage sensor this pile car alarm can distinguish small bumps from aggressive move