You can use the SED linux command to search and replace a string within all files inside a directory:
This example replaces all occurrences of fast with slow in file names that end in .htm:
$ find ./* -name ‘*.htm*’ -type f -exec sed -i ‘s/fast/slow/g’ {} \;
Johnson Controls M4-CGM09090-0 Controller CGM09090 Metasys Ry-12541
$375.00
Johnson Controls EASYIO FW-08 WiFi BMS/BAS Controller - NEW
$150.00
JOHNSON CONTROLS TEC3630-14-000 Thermostat Controller
$359.99
Johnson Controls T4002-201 Pneumatic Thermostat (Direct Acting)
$18.00
Johnson Controls F4-CGM04060-0 General Purpose Programmable F4 Controller
$95.00
Johnson Controls A421ABC-02C Line-Voltage Type 1 Temperature Control
$91.81
Johnson Controls F4-CGM09090-0 Controller CGM09090
$249.00
Johnson Controls AS-LCPKEY-0 DX9100 service access tool
$35.00
JOHNSON CONTROLS FACILITATOR HVAC CONTROL FA-unit110-1 WTN0141 REV B
$71.00
johnson controls t-4002-201 Thermostat Direct Acting Single Temp Horizontal F Di
$49.00