On the TTn guns the hammers ( rebounding type) are the safeties.
"Remington" Spartan, AKA Baikal - Russian & Wyatt Earp - Italy , are hammer guns with manual safeties
( the Chinese "Century" does as well )
Both the Stoeger & The Baikal Box-lock can be made manual by shortening the rod about 1/8 " or so , easy job