1. Ceev nrooj screws yog tsuas yog siv rau kev ncua thiab kho cov cua txias kav dej, kav dej, kav dej fais fab, qab nthab, thiab lwm yam.
2. Twist-type flat-headed non-standard screws tuaj yeem siv rau ntawm cov cement pob zeb, cib ntsa, thiab hollow cib los kho cov khoom siv hauv chav dej.
3. Sab hauv cov hniav uas tsis yog-tus qauv screws yog siv los kho cov marble, cov kav dej, cov kav dej hluav taws xob, thiab kaum hlau.
4. Cov ntsia hlau tsis yog qauv, feem ntau yog siv los kho cov suab rwb thaiv tsev phab ntsa thiab cov khoom siv hauv chav dej.
5. Cov ntsia hlau uas tsis yog-tus qauv ntawm cov hniav sab nraud yog siv rau cov hlua khi ntawm cov kav dej, cov kav dej hluav taws xob, thiab cov cua txias, thiab kev kho ntawm ntau lub kaum ntse ntse hlau thiab hom hlau.
6. Twist-type tes tsho tsis-standard screws yog siv los kho cov teeb pom kev zoo, lub teeb steel zaj skeleton, thiab cov khoom siv hauv chav dej.
7. Honethal non-standard screws yog tsim rau kev kho ntawm lub qhov rooj thav duab, txee thav duab, cov khoom siv hauv chav dej, thiab cov khoom siv phab ntsa.