1. Three Basic Dimensions
Pitch, Roller Diameter and Inner Width are known as the "Three Basic Sizes of Roller Chain." When these three sizes are similar, roller chains and sprockets are dimensionally compatible.
2. Basic Parts
Link Plate
The plate may be the component that bears the strain placed on the chain. Usually that is a repeated loading, occasionally accompanied by shock. As a result, the plate must not only possess great static tensile power, it must also hold up to the powerful forces of load and shock.
Pin
The pin is at the mercy of shearing and bending forces transmitted by the plate. At the same time, it forms a load-bearing part (alongside the bush) when the chain agricultural Chain flexes during sprocket engagement. Therefore, the pin needs high tensile and shear strength, resistance to bending, and must also have sufficient stamina against shock and use.
Bush
The bush is at the mercy of complex forces from all parts, especially from the repetition of shock loads when the chain engages the sprocket. Consequently, the bush needs incredibly high shock resistance. Furthermore, the bush forms a load-bearing part together with the pin and as such requires great wear resistance.
Roller
The roller is at the mercy of impact load as it mates with the sprocket teeth during engagement of the chain with the sprocket. After engagement, the roller changes its stage of contact and stability. It is held between the sprocket the teeth and bush, and moves on the tooth face while getting a compression load. Therefore, it must be resistant to put on and still have power against shock, fatigue and compression. (RS25 and RS35 are bush chains , nor have rollers).
Roller Link
Two bushes are press match two roller link plates and rollers are inserted to permit rotation around the exterior of the bushes during operation. This is actually the same for single and for multi strand chains.
Pin Hyperlink and Intermediate Plate
The pin link contains two pins that have 
been press match two pin link plates. In case of multi-strand roller chain up till size 08B, an intermediate plate is usually added to the pin hyperlink. In case of multistrand roller chain above size 08B, two intermediate plates are put into the pin hyperlink. The intermediate plates are slip fit for regular roller chain and press suit for SUPER roller chain.