For applications requiring polarisation (use of plugs of different sizes) to prevent insertion of incorrect equipment Littel-Plug® phone plugs featuring a sleeve and tip diameter of .206 inches are available.

Mate with Number S128 Extension Jax® and S11 Littel Jax® jacks.

Number S260 used interchangeable with Military Type M642/51 (Switchcraft Number 480) plugs.