The #118 coupler will work anywhere a NO.5^®, #28, #38, #58, #118, #119 & #148 Coupler will work. 

The #118 "SF" Kadee^® Magne-Matic^® WHISKER^® Coupler features a All Metal Coupler, Metal WHISKER^® Centering Spring. The #118 "SF" Coupler may be mounted in Manufacturers cast-on coupler pockets or any of our HO-Scale draft gear boxes (except #233 30-series gear box). 
25 pair per package

It is not recommended to use a metal coupler directly on a metal surface or in a metal draft gear box to avoid the possible electrical crossover or shorting that may cause damage.