Craig 4501 Early 1970s Vintage Calculator, Kilxon keys, Optostic LEDs, works.

Description

This item is a Craig 4501 Electronic Calculator, made in the U.S.A.  It is in excellent condition and fully functional.  All the "Klixon" keys work fine and all have that consistent TI "Klixon" feel and sound, even after almost 50 years.  The Bowmar 9 position (8 digits plus sign) "Optostic" LED display is in perfect condition and still very bright.  Cosmetically this calculator is in excellent condition.  The internal NiCad batteries have been replaced with six Tenergy 1000mAh cells that have been fit into the original six position AA battery holder that screws into the bottom half of the calculator.  It comes with the zippered carrying case which is in excellent condition inside and out and also comes with the Model B901-077-4 wall charger with the very odd polarity plug that fits perfectly into the calculator.  The operating instruction booklet is in excellent condition, no missing pages, tears, rips or writing inside.  All pictures are of the actual items you will receive.  Ships via USPS Priority mail with tracking.
The 4501 was Craig's first calculator model and was actually made by Bowmar for Craig.  It was the same design as the Bowmar 901B.  Both were considered to be the first true hand held calculators made in the U.S., being introduced in late 1971 and early 1972.  This calculator uses the "Optostic" red LED display made by Bowmar.  Bowmar was actually looking for a market for their "Optostic" display and started making calculators as a way to sell their LED displays.  When you examine the individual segments of the "Optostic" numbers, you can notice that each of the 7 segments is actually 4 very small LEDs lined up in a row to make a longer line segment.  Bowmar used the Texas Instruments "Klixon" keyboard design so called because the keys had a very distinctive click, feel and sound when pressed.  They also used one of the many recently released single chip calculator ICs made by Texas Instruments.  Within a few years Bowmar was the largest calculator company in the world making their own calculators as well as selling them to other companies to label as their own including Craig, Commodore, Sears, Radio Shack and others.  Of course this did not go unnoticed by Texas Instruments who also started making calculators using their single IC chip designs and eventually Bowmar succumbed, filing for bankruptcy in 1976.