0-10KHz Pulse Frequency Delay Module, DC 12V Pulse Counter Module High Level Trigger Relay Module for Motor Speed Sensor (Without Shell): Amazon.com: Industrial & Scientific
High Speed Counter Module (1 encoder) PLUS - EZIOP-HSCM2
Fanuc 829-4-0 REV. D Counter Module
2.4GHz Counter
LCD DVM and Counter modules Displays
3 Digit Digital Objects Counter With Laser Module - BuildCircuit.COM
CD4026 up counter for Arduino and NE555 from BuildCircuit on Tindie
Mini LCD Digital Counter Module DC/AC5V~24V Electronic Totalizer with NPN and PNP Signal Interface 1~999999 Times Counting Range - Walmart.com