Aluminum Hollow Plunger Cylinder. $1.00. RARH1002, 1001 kN Capacity, 50 mm Stroke, Double-Acting, Aluminum Hollow Plunger Hydraulic Cylinder. Aluminum Hollow Plunger Cylinder. $1.00. RARH1006, 1001 kN Capacity, 150 mm Stroke, Double-Acting, Aluminum Hollow Plunger Hydraulic Cylinder. Aluminum Hollow Plunger Cylinder.