The Sentry V2 is an Intelligent phone call blocker which can block almost all spam calls. All material and chip are tested by CE,FCC.

There are useful multi-functions with Sentry call blocker but easy to operate,so it is the best blocker for senior people who doesnt want troublesome setttings. If you are considering buy one for parents, then this is the best choice.
Generally 3 functions are included:

Firstly,BASIC MODE- when the voice is off, only the Blacklist work but not the Whitelist; In this mode, if you want to block numbers, then press REJECT,all calls with call id will be blocked.
Secondly,block the private and hidden numbers; When the hidden number is located,keep pressing REJECT until BLOCK NO CID shows,then all hidden numbers are blocked.
Finally,use the white list(choose warning voice from A/B/C on Sentry),all new calls need to press "0" and automatically saved to the White list forever(unless you remove it or change to blacklist).

The perfect thing for Sentry blocker is the voice reminding function; it stops 99% of the spam calls; with this blocker, all you need do is to set a white list first for your friends, families and company numbers, then rest frauds will be automatically stopped just by a voice reminding. It is really a polite and useful way to reject those calls. If you dont know which block to buy, try this one and you will be happy for your choice.

• There is a kind voice reminding for the caller to stop if his calls is not welcomed; Block all spam calls, including those not on the Black List.
• If the caller press "0" and get through the call,then his number will be automatically saved to White list forever(unless you remove it or change it to blacklist).
• Eays to block private and hidden numbers: Press and hold REJECT BUTTON until BLOCK NO CID appear on Sentry,all calls without showing call id will be blocked.
• Turn the warning voice to OFF(enter to BASIC MODE: white list don't work,blacklist still work),then Sentry will allow all unlisted calls to pass through while still blocking the blacklist calls.
• You can use BASIC MODE while waiting for an important call from unknown numbers.

There is a kind voice reminding for the caller to stop if his calls is not welcomed; Block all spam calls, including those not on the Black List.Cheeta