To make a long story short I am trying to put together a oxy/act cutting rig for some projects around the house. Just hobby type stuff nothing really major. I bought my house a year ago it had a shed behind it that had some oxy/act cylinders in it 3 actylene of various sizes and 2 oxygen cylinders that are the same size. So I been eyeing the cylinders and 1 oxygen is out of date and 2 acetylene cylinders are out of date. Then I also find out that if the cylinders have a company name on them no one will exchange or fill them 1 acetylene has a name stamped on it that I dont recognize 1 oxygen cylinder has a name in raised letters on the neck ring. The other oxygen cylinder has nothing on it no name or anything but it is out of date. So I have to get it tested then maybe possibly filled 1 of the larger acetylene cylinder has nothing and it is out of date. Then there is this smaller acetylene cylinder that is not within date and has a weird valve on top that will not accept a normal acetylene regulator what is this acetylene cylinder for?