
Take, credit card size 0.8mm.
Tags are waterproof
The most commonly used 125 kHz transponders - also called tags - is of the "read only" type - that is, fabricationen they are provided with a unique ID code of up to 40 bits can not be changed.
Tags are available in a variety of different configurations. Eg. round pieces of various sizes and formats, fobs and credit cards. Here only the most popular types.
125kHz RFID TAG for adhesion
Dim: 20 x 3 mm
3M tape
black
TAG is waterproof
Tag, key ring
target: 35 x 2 x 4 mm
with engraved UID code
tag is waterproof
125kHz RFID TAG
credit card size 0.8 mm
sequential ID
TAG is waterproof
125kHz TAG
rectangular, transparent plastic
Dim: 20 x 25 x 0.7 mm
TAG is waterproof