Certainly not "essential" tools to have, but definitely useful tools which I'm always glad to have purchased (especially for older French bikes and components).
Specialites TA _ ref. 24 socket tool:
A very precisely sized tool, this one is part of my old TA tool kit. This is perfect for #25 chainring mounting bolts and especially nice for the old TA "domed" bolts. This is cut flush at the opening as opposed to modern sockets which are often tapered for a quicker fit over hex bolts or nuts. This means there is much less chance of the tool slipping off and rounding the corners of old TA hex-head bolts... which always seemed to be made of soft steel and were poorly plated.
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VAR #19 - open end wrenches:
Large thin wrenches in uncommon sizes... 22/24 mm & 26/28 mm. Sometimes exactly what is needed for bottom bracket cups (such as Stronglight) on old French bikes.
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BOB HANSON, ALBUQUERQUE, NEW MEXICO, USA