Measurements are from buckle to buckle, you will need to allow an extra 1" compared to your normal girth size because of the fleece liner.
If the size you need isn't instock please see here - as part of the core range this can be ordered with delivery in 3 to 4 weeks.
The Pony Special Girth
These girths were developed to accommodate ponies with very narrow-standing front legs, small and/or short backed horses with rounded bodies. Length is always speciﬁed from buckle end to buckle-end.