Bosch 11304-no data tag-034 or 139? How can identify?

[TedGeneralRental]

As the title line says...I am trying to identify my hammer without a data tag. I need a service pack, but don't know which one it is.

[WJA]

Hello TedGeneralRental,

The motor assembly between the 034 and 139 is one of the main differences, but that is a little difficult to tell without disassembling the tool. There is one difference on the outside of the tool which will tell them apart though. It is the guide tube ( item #37 on both the part diagrams). By looking at both diagrams you will be able see the differences, and hopefully identify your hammer.

Hope this helps,
WJA

[GeneLanzl]

HeyTedGeneralRental,

The outside of the piston housing on the 139 has very deep ridges while the 134 is smooth just like the drawings show. Hope this with WJA's explanation helps.