The RNID Contact Mat is a very handy device to have around the house if you have toddlers or people with hearing disabilities. The slightest of pressure is detected by the mat and then transmitted onto a vibrating pager or a flashing and audible receiver, thus alerting you about it. Functionally you can place the mat at the doorstep so that you can be alerted when your mischievous bundle steps out unattended.

You can check out the details for the RNID Contact Mat here. It costs £31.90 ($64).
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