2.7 Modifications to car design:
2.7.1 General
The complete car is divided into three types of part.
Type 1: These parts must be supplied by the manufacturer and used exactly as supplied. Repairs may be carried out only by the manufacturer.
Type 2: These parts are Type 1 parts with specific restrictions. Only the modifications indicated in the homologation may be carried out. Repairs are allowed only in the range described in the homologation.
Type 3: These parts are unrestricted, provided that they are used as designed by the manufacturer and do not fulfil any additional function.
The adding of colour or thin adhesive film up to a thickness of 0.5 mm is not considered as a modification, provided that the colour or film fulfils only an optical function.
2.7.2 Standard mounting parts
Standard mounting parts, such as screws, nuts, bolts, washers and lock washers, are considered as Type 3 parts unless specifically mentioned in the homologation. They may be replaced with equivalent or superior standard parts.
The thread type, size, length and pitch must remain the same.
The use of locking wire is permitted.
Any type of standard mounting part which has an influence on the car set-up is considered as a Type 1 part unless specifically mentioned in the homologation.
Only Type 3 washers may be removed.
Washers may be added only for facilitating and improving mechanical installation. They may influence the set-up of the car only when specifically mentioned in the homologation.
2.7.3 Protections
Heat protections, mechanical protections (such as abrasion protection or tape) and protections for driver comfort may be added, provided that their sole function is the protection of the relevant element and unless specifically mentioned in the homologation.
2.7.4 Bodywork
The modification of bodywork parts and bodywork supports is allowed only to ensure proper installation despite manufacturing tolerances.
2.7.5 Quick couplings
The use of quick couplings for brake, clutch and fuel lines is allowed, provided that FIA-approved dry couplings are used.