Where precise ratios (to three decimal places) are required then our “Duplex” box comes into its own. Originally designed by Smiths Industries as a corrector gearbox for Tachograph installation this gearbox can be used as an “in-line” method of obtaining the correct revolutions. Ratios range from 0.20:1 to 5.00:1 both increasing and decreasing.

It is made of a two piece alluminium housing providing maximum protection against water/dirt ingress. The input into the box is by a spindle connected to a gear train and output is through a second spindle opposite the input.

These are normally fitted into heavy-duty cables to correct the calibration of Speedometers and Revolution Indicators

They have a standard input and output

Input is M22 x 1.5 left hand thread with 3 mm slot

Output is M22 x 1.5 right hand thread with 2.75 mm spade

We can offer over 500 different ratios. Please contact us with your requirements.

Price (GBP)
ex VAT