This is one of a large number of different DNP models that I have seen which have the code number 'M1270' stamped on the inner parallelogram plate.

In this case, it is a long cage (75mm, or 'GS' in Shimano-speak) model with something of the style of a mid-range Shimano mountain bike gear, perhaps an Exage of some sort.

• Derailleur brands: DNP
• Country: Taiwan
• Date of introduction: 1995?
• Date of this example: unknown
• Model no.: M1270
• Weight: 281g
• Maximum cog: 34 teeth?
• Total capacity: 34 teeth?
• Pulley centre to centre: 75mm
• Index compatibility: 6 speed?
• Chain width: 3/32”
• Logic: top normal
• B pivot: sprung
• P pivot: sprung
• Materials: steel pulley cage and parallelogram plates, aluminium B-knuckle and plastic P-knuckle