Attention points for purchasing rebar coupler:

1. Random sampling for testing should be conducted. 5% of each batch should be tested, and the acceptance rate should be higher than 95%. If the qualification rate is lower than 95%, a second sampling should be carried out with the same number of new samples.

After two rounds of testing, if the average qualification rate is still above 95%, then the batch of sleeves is considered qualified. If it is still below 95%, each sleeve in that batch should be individually tested.

2. The manufacturer of the rebar coupler should have a certificate of conformity and material specification.

3. The couplers should be tested for their ability to be screwed in.

4. Both ends of the couplers should have plastic protective caps.

5. The plastic protective caps should be marked with the same specifications as the rebar coupler.