Hi Arif,

Most probably your transducer is Mitsushita brand as your mentioning Rx/Tx suggests. Because I bought 2 pairs of transducers from my local market in Karachi - Pakistan.

Most probably yours is the same. Alumininum body Round shape approx. 1 inch dia with black fine grating face. Marked with Rx on one and Tx on the other.

Because our indo/pak markets are stuffed with the same kind of crap by the agents from singapore / taiwan.

Its 40KHz Piezo transducers. Useless, doesn't work beyond 10 foot at maximum.

Hope it helps.

Babar