When people say ‘scuba fabric’ many think of the tradition neoprene fabric wetsuits are made from, however scuba is more malleable and thinner (it also doesn’t have that layer of foam wet suits have) so don’t let the name put you off.
It is in fact a double knit fabric, like a Ponte Roma – however it would be unfair to compare the two as they are often made from different compositions. As a general rule Scuba fabrics tend to be made from Polyester, whilst Ponte Roma fabrics are usually from viscose and lycra.
They also have different properties, while Ponte Roma has stretch, scuba jersey is well known for having both good stretch and recovery. Something that you will appreciate, if like me you tend to accidentally pull/stretch fabrics while sewing them!