638 is a high quality battery from Numax. The cold cranking current of the battery is 900 A. The dimensions of the product are 510 x 174 x 205 mm. You should use the dimensions of your old battery as a guide for your selection. Durable Wet technology for your vehicle The 638 has a capacity of 143 Ah. The higher the value, the more electrical charge can be stored in the battery. Wet batteries like the 638 are suitable for heavy duty vehicles with everyday energy needs. They offer reliable performance for commercial use. The technology of this battery supports starting and power requirements in heavy duty applications. You should consider this when buying Before you buy, check that the circuit and polarity of your new battery are identical to the values of the old model. The circuit shows whether the positive pole is on the right or left of the battery. To determine this, position the battery so that the poles are facing you. With the 638, the circuit is 0, so the positive pole is on the right.