The Montblanc two-digit model number pens/pencils were replaced in 1968 with the Classic line-up. The pens/pencils reverted back to a three-digit numbering system.  

The No. 151 mechanical is in the Meisterstuck tier. The pen features an 18k "twice heavy gold electroplated fittings (double processed)" as noted in the 1975 Montblanc catalog. The pencil features the "bishop's mitre" cap band similar to the 120/121 fountain pens. This pencil was sold with Montblanc's Lifetime Guarantee. This was the top of the line mechanical pencil in the 1960s-1970s.

The pencil is in (C) Good condition. The lead appears to be 0.7 mm. 

- Manufacturer/Model: Montblanc Meisterstück No. 151
- Year of Manufacture: 1968-1979
- Color: Black, Gold
- Material: Resin
- Filling System: 0.7 mm lead
- Condition Rank: (C) Good
- Country of Manufacture: Germany

Condition Rank Guide:
-N: Item is in New Old Stock condition (NOS). Shows little to no signs of use apart from some minor handling wear.
-A: Item is in Excellent condition. Micro-scratches can be seen on the barrel, cap, and/or grip section. No noticeable scuffs, chips, or cracks.
-B: Item is in Very Good condition. Minor scratches and scuffs can be seen on the barrel, cap, and/or grip section. No chips or cracks.
-C: Item is in Good condition. Moderate scratches and scuffs can be seen on the barrel, cap, and/or grip section. No chips or cracks.
-D: Item is in Fair condition. Heavy scratches and scuffs can be seen on the barrel, cap, and/or grip section. May have small chips or cracks. See description.
-F: Item is in Poor condition. Item is not functional. For parts or repair only.