SLF71905ETP4SULSuper-Precision Angular Contact Spindle Bearing, 25x42x9 mm, 25° Contact Angle, Phenolic Cage, Universally Ground Light Preload, P4S (ABEC 7/9)

Product Description

What this part is

This is a super-precision angular contact ball bearing in the 25 mm bore x 42 mm outside diameter x 9 mm width envelope — the ISO 71905 size.

Decoding the designation

The suffixes decode as: E is a 25 degree contact angle, T is the phenolic cage, P4S is the super-precision tolerance class (ABEC 7/9), and UL means universally ground with light preload.

What these specs mean in practice

A 25 degree contact angle carries substantially more axial load than the 15 degree alternative in the same envelope, and holds a spindle more rigidly against thrust, at the cost of some speed capability — so it is the choice where a light-section spindle still has to take real cutting thrust. The 42 mm outside diameter on a 25 mm bore makes this a thin-section 719 series bearing, chosen where radial space is tight — typically small grinding spindles, high-speed routers, dental and medical handpieces, robotics joints and instrument spindles.

Fitting notes

Universal grinding means any two of these bearings mount together back-to-back (DB), face-to-face (DF) or in tandem (DT) and reach the specified light preload without shimming or custom grinding, so one part number covers every arrangement.

Interchange guidance

SLF is a German precision bearing manufacturer specialising in spindle and machine-tool bearings. This part also cross-references to Timken 2MM9305WI CR SUL.