7 extension rods in lengths 10mm,15mm,20mm,40mm,60mm,80mm,100mm. Make any combination up to a total of 315mm.5mm Spacing Length
Length 10 mm: 10mm long,
Length 15 mm: 15mm long,
Length 20 mm: 20mm long,
Length 25 mm: 10+15=25mm long,
Length 30 mm: 10+20=30mm long,
Length 35 mm: 15+20=35mm long,
Length 40 mm: 40mm long,
Length 45 mm: 10+15+20=45mm long,
Length 50 mm: 10+40=50mm long,
Length 55 mm: 15+40=55mm long,
Length 60 mm: 60mm long,
Length 65 mm: 40+10+15=65mm long,
Length 70 mm: 10+60=70mm long,
Length 75 mm: 15+60=75mm long,
Length 80 mm: 80mm long,
Length 85 mm: 60+10+15=85mm long,
Length 90 mm: 80+10=90mm long,
Length 95 mm: 15+80=95mm long,
Length 100 mm: 100 long.
Length 105 mm: 90+15=105mm long.
......
Length 315 mm: 100+80+60+40+20+15=315mm long.

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