The Oxy1 was the very first yo-yo (not mass produced) by Oxygene. It was a slimline aluminum yo-yo with rubber O-rings on the rims, in addition to a titanium axle with a ball bearing, an adjustable string gap and a starburst response system milled into the halves. It was handmade by founder Carlo Menon in 1997.
The Oxy0 was an earlier prototype also handmade by Carlo Menon. Physically, it is the same as the Oxy1, but there is one key difference; The Oxy0 did not have the milled starburst like its brother did.