Starter set · 25 bits · C3
MNA RS-25P4, 25-piece set, 1/4 in shank
Twenty-five bits, an American carbide classification, and a compatibility list that names a rival on this shelf.
Every figure below names its source. Each one is a manufacturer
specification read off the listing itself. The judgments are ours.
It names a rival on this shelf
Ten router brands: MNA, Kowood, Bosch, DeWalt, Makita, Milwaukee, Porter &
Cable, Skil, Ryobi, Black & Decker.
Kowood has two sets of its own on this shelf.
The list is really one sentence — this fits any router with a 1/4 inch collet —
and the striking thing is that it is true. Bits and routers are interchangeable
across brands in a way almost nothing else in a workshop is.
That fact is worth more to a buyer than any of the ten names.
Shank before everything
A router bit is held by its shank, and the collet that holds it has one size.
A quarter of an inch is 6.35 mm (0.25 in). Eight millimeters is eight. A 1/4 in bit drops
loose in an 8 mm (0.31 in) collet and an 8 mm (0.31 in) bit will not enter a 1/4 in one — and a
collet is a precision clamp, not a hole: there is no ring, no bush and no adapter
that makes either fit the other safely.
Which is why the two halves of this shelf cannot be mixed. Every American listing
here is 1/4 in; every European one is 8 mm (0.31 in). The published Spetool page on this
shelf states the rule in one line, and it is the most useful sentence on the
shelf.
The American dimension and standard
Which is the most useful claim on this page and the least specific.
It means the shank, mostly: 1/4 and 1/2 inch rather than 8 and 12 mm (0.47 in). It also
means the profiles are in fractions of an inch rather than whole millimeters,
which matters when a drawing is dimensioned one way and the cutter the other.
C3, named with its system
American industry classification C3 — which is more than most listings manage, and
it is the second C3 on this shelf.
C3 is harder and more wear resistant, for straight cuts in abrasive sheet goods.
C2 is tougher and chips less, for a profile bit taking side load against a
bearing.
A 25-piece set contains both kinds of work, so a single grade is a compromise in
one direction or the other.
Four of the seven American listings here publish a grade. None of the seven
European ones does.
Twenty-five bits, none named
Stated: a great variety of the most popular carbide-tipped bits.
Most popular is a selection criterion, not a contents list — and the four or five
bits that will actually get used are the whole question.
The published ENT page on the European half of this shelf is in the same
position, and makes the same honest case for buying a set anyway.
Availability
Read on the day this page was built: $39 at the American Amazon shop.
Read from Keepa on the day this page was last revised; stock and price both move without notice.
Prices quoted in this text were read on 2026-10-07. The live price is at the top of the page.
