any one?

PNP type is best.
(gives pulse when something is detected)

Tks

I got all my sensors from RS Components, a hall-effect sensor was £17 instead of £40 from the people that sold the data logger - for exactly the same sensor from Honeywell.

ABS sensor off donor, its free !

okey but we are targeting something digital incl. hysteris not something purely analog like that sensor.

Tks