The 80387SL is a coprocessor designed for use in systems based on an Intel 386SL CPU. The 386SL is derived from the 386SX. It is a static CHMOS IV design with very low power requirements that is intended to be used in notebook and laptop computers.
The 387SL, introduced in early 1992, has been designed to accompany the 386SL in machines with low power consumption and substitute the 387SX for this purpose. It features advanced power saving mechanisms. It is based on the 387DX core, rather than on the older and slower 80387 core (which is used by the 387SX).