Hi. I have for sale a never used Marzocchi Roco Coil / Air piggy back / reservoir. Marzocchi part number: 553013NZ10. Total length of this reservoir is: 64mm. Internal diameter is 25,5mm. Outer thread diameter is: 29,85mm. Price is for one not all as in photos. I don't know if it fits all years / lengths etc. If You need any dimensions for comparison please send me a message.