Miniguide ultrasonic obstacle detector Product features Hand held ultrasonic obstacle detector. Product details device vibrates when an obstacle is detected vibration frequency increases as obstacle becomes closer five settings ranging from 0.5 metre to 8 metres the Miniguide is intended as a secondary aid to support traditional aids such as cane and guide dog. the Miniguide cannot detect drop off points such as steps and kerbs supplied with one CR123A battery. Replacement batteries available from RNIB (product code CP21). Please Note: RNIB does not guarantee batteries. Dimensions: Width:4cm (1.57") Length:7.9cm (3.11") Depth:2.2cm (0.87") Product code: ME10 Product instructions (Word, 134.50KB) Price £299.99 inc VAT £249.99 ex VAT Blind and partially sighted customers will not pay VAT from Vanessa The Google Girl. my skype name is rainbowstar123