Are you trying to choose between the Fisher AG7 and CH4 space pens? They look so much alike, but there are some differences in shape and price… so how do you choose? This article will help you tell the difference between these two pens and to find that one that’s right for you.
Have no doubt about it, these two are Fisher’s icon pens. They are the ones people associate with the space missions, the ones that — as story would have it — cost millions of dollars to develop when the Russians just used a pencil.
History of the Space Pens
The AG7 pen was patented in 1966 by Paul Fisher of Fisher Pens as the Anti-Gravity pen (hence “AG”). It was sent along with the Apollo 7 space mission in 1968 after over a year of testing by NASA.
The CH4 didn’t come along until 1981. The Chrome Plated Shuttle Space Pen became, and still is, the standard space pen used by NASA.
That’s a highly truncated history, but the point is this: the AG7 is the original space pen while the CH4 is a newer model that still manages to have excellent space credentials.
AG7 vs CH4: The Big Differences
- The AG7 has an aggressive taper where the CH4 is practically straight from top to bottom
- The AG7 has a cleaner “click” action and a slightly better built quality
- The AG7 is heavier 23.8g vs 19.5g (when empty)
- The AG7 has a nicer clip, made especially for the pen where the CH4 has a cheaper stamped clip
AG7 vs CH4: What’s The Same
Despite some notable differences, a lot of the qualities of these pens are the same.
- Both use Fisher’s PR4 pressurized refill
- Both are made of chrome-plated brass
- Both are made in the USA
- Both are “guaranteed against all manufacturing defects” and covered by Fisher’s excellent support services