The DA-SR is specifically designed as a drop-in decoder for Atlas, Kato, Life-Like, and Walthers. Remove the small black wire retainers from the existing light board in the loco, transfer the wires to the DA-SR decoder. Move the wire retainers on to the new board.
The diagram below is from a typical atlas locomotive
This is a picture of a standard atlas DC board with the wire retainers factory installed. notice the bare wire just slips into the hole.
Decoder version 3.5 (Rev D) Dimensions: 2.850 x 0.65 x .125 inches - 72 x 17 x 3.2mm
Atlas GP38, GP40, RS1/2/3, C424/5, GP7, RSD4/5/12, C30-7, U23B, U33/36C
Athearn "Genesis" series locomotives; F7, F3, SD70, SD75, SD80, etc...
Kato GP35, SD40, C44-9W Stewart AS16, F3A, F3B, F7A, F7B, F9A, F9B, U25B
This is an EPF (extended packet format) decoder supporting:
Silent Running TM motor drive
Improved DC operation (with lighting effects)
Torque Compensation (dither) for ultra smooth low speed performance
Programmable Start, Mid and Maximum speed works for all speed modes
Motor rating 1.3 Amp continuous, 2 Amp peak (stall)
All five function outputs have lighting effects generators
Select from 15 different lighting effects (Mars, strobes, beacon, flicker, etc)
Lighting outputs can be mapped to different functions
Uploadable speed table interpolated to 128 speed steps
Decoder assisted consisting
Support for all forms of DCC programming
Decoder programming lock mechanism
Brake on DC feature assists automatic train control