A 4500 is string wrap only, the 4590 is string & NET. Wish mine was a 4590,I have not found a way to convert a 4500 to net. M&W balers are now owned by Arts Way mfg. I got my 4500 used about 1500 rolls through it for $2250.00. For the last 4 years it has been the most trouble free baler that I have ever seen. Replaced 1 hyd hose.