The G-Shock's urethane watch band features a rubbery texture, but it is in fact much stronger than rubber. The band itself serves as a shock absorber, which gives the watch added protection. The urethane band is "an ideal balance between shock resistance and comfortable wear-ability."

If the G-Shock watch does not have an adjustable watch band, you need to replace it completely. Locate the spring bars near the base of the watch that holds the band in place. Use a spring bar removal tool to apply pressure to the spring bar and remove the band from the watch. Place the spring bars in the slots of the replacement band, and use the spring bar removal tool to replace the spring bars into their respective sockets. Pull lightly on each end of the band to ensure it is firmly secured to the watch.

Measure your strap width:

Size indicated below is (Fitting width)x(Maximum strap width)
When selecting size/colour in option, use fitting width.

Model A:
Thickness: 2.35mm
22mm fit Samsung Gear S3, Pebble watches

Model B:
Thickness: 2.35mm
18mm strap fit Casio AW302, DW2500, LED100, DW400, PGW92
20mm fit Casio CA-53W W-720 W-520U CA-61W DB-57
22mm fit Casio AMW-110, AMW-320, AMW-S320, AMW-330, AMW-380, AMW-360, AMW-370
22mm fit Samsung Gear S3, Pebble watches

Model H:
Thickness: 2.5mm
Fits:GA-100-1A1W
GA-100-1A2W
GA-100-1A4W
GA-100C-1A3
GA-100C-1A4
GAC-100-1A2D
GAC-100-1AD
GD-100MS-1
GD-100MS-3
GD-100-1A
GD-100-1B
GD-100SE-1
GD-100GB-1ER
GD-100HC-1
GD-100GB-1
GDF-100-1A
GDF-100-1B
GDF-100BB-1
GA-110-1A
GA-110-1B
GA-120-1AD
GA-120BB-1AD
GA-120BB-1AW
GA-300-1AD
G-8900-1W
GR-8900A-1
GR-8900-1
GD-8900A-1
GD-8900-1
GW-8900-1
GW-8900A-1

Model J1:
Thickness: 2.5mm
Fits: 9052 series
AWG-M100F-1BD
AWG-M100F-1AD
AW-590-1AW
AW-591-2AW
AW-591-4AW
G-7700-1W
G-7710-1W
AWR-M100-1AD
AWG-M100-1AD
AWG-M100A-1AD