type 1: tapped bore, vibration ground with a half-matt finish;
type 2: tapped bore, polished and brushed with half-matt finish;
type 3: right through bore, polished and brushed with half-matt finish;
type 4: tapped bore, polished;
cover plates can be purchased separately (for type 1, 2, 3: AK02.0817.1301, AK02.1017.1501, AK02.1517.2301, AK02.2017.3001 and for type 4: AK02.4217.0000);
type 1 en 2: including hexagon head screws (DIN 933) and washers (DIN 125);
type 3: including bolts (DIN 912), nuts (DIN 934) and washers (DIN125);