The twin cylinder engine has slip eccentric reversing, the geared bogies each shaft driven from either end of the crankshaft.
| gauge | Gauge 1 & smaller |
| length/inches | 15 1/2 |
| width/inches | 4 1/2 |
| height/inches | 7 1/2 |
| weight/kg | 3 |
| wheel material | steel |
| axlebox type | plain bearing |
| cylinder material | gunmetal |
| valve type | slide |
| valve gear | slip eccentric |
| lubricator type | displacement |
| boiler type | Shay T-boiler |
| boiler material | copper |
| boiler construction | silver soldered |
| safety valve(s) | 1 |
| safety valve type | spring |
| hand pump | 1 |