You control the pressure until desired effect with the EZ squeeze handle with pressure release valve.

Features:

Material: Silicone (Soft Base & Hose), Polystyrene (Clear chamber), ABS (Gauge, Pump, Remote & Bullet)
Size: 11.75b (Total length), 2.5b to 2.6b (Cylinder diameter at base), 7.87 (Insertable length)
2 AA batteries