This listing is for one set of brand new CP Pistons for the Subaru EJ20 engines from the Impreza WRX 

Included = 4x Pistons + 4x Wrist Pins + 4 Rings + Locks 

Bore Size = 92mm (3.622") 

Compression = 8.5 
Pin Size = 23mm (905-2500-18CP1S) 
Stroke = 75mm 
Rod C-C = 130.5mm 
Compression Height = 32.6mm (1.285") 

Dish Volume = -8.15cc 
Weight = 359grams 

Locks = 905x055-SUB 

Rings = RS1313-3622-0 

Part Number = SC7399 (ID = 4173)