Designation	No.7a
Bore	1 inch
Stroke	1 inch
Configuration	Vertical single cylinder
Height	7 1/2 inches
Extra equipment	Drain cocks Displacement lubricator Reversing gear
Taps required	4, 5, 7 BA 5/32, 3/16 x 40 tpi 1/4 x 32 tpi 1/4, 7/16 x 26 tpi
Notes	The vertical version of the No.8, these two engines make up a larger version of the 10V/10H pair of engines. There is an obvious family resemblance in all four engines with their trunkguide crosshead and overall proportions.